acidic
US /əˈsɪdɪk/
UK /əˈsɪdɪk/
- Adjective
- Containing acid
B1Moreall along
US /ɔl əˈlɔŋ/
UK /ɔ:l əˈlɔŋ/
- Adverb
- From the beginning; all the time.
- Phrase
- In a line parallel to something long.
A2Moreammonium
US /əˈmoʊniəm/
UK /əˈməʊniəm/
- Uncountable Noun
- A chemical derived from ammonia
- A salt or compound containing the NH4+ ion, often used in fertilizers.
B2Morearrow
US /ˈæroʊ/
UK /ˈærəʊ/
- Noun
- Symbol used on road signs to show direction
- A long pointed piece of wood shot from a bow
B1Moreas with
US /æz wɪð/
UK /æz wið/
- Preposition
- In the same way that something happens or is true of something else.
A1Moreaware
US /əˈwɛr/
UK /əˈwɛə/
- Adjective
- Knowing or feeling that something exists
A2TOEICMoreback down
US /bæk daʊn/
UK /bæk daun/
- Phrasal Verb
- To admit you were wrong; stop claiming
A1Morebeta
US /'beɪtə/
UK /'bi:tə/
- Noun
- Test version of a product or software
B2Morebond
US /bɑnd/
UK /bɒnd/
- Noun (Countable/Uncountable)
- Rope, chain or other thing used to tie someone up
- Closeness that is shared between people or groups
- Verb (Transitive/Intransitive)
- To develop a close relationship with
- To become joined or connected, e.g. using glue
A2TOEICMorecarbon
US /ˈkɑrbən/
UK /'kɑ:bən/
- Uncountable Noun
- Chemical element with an atomic number of 6
B1Morechemistry
US /ˈkɛmɪstri/
UK /'kemɪstrɪ/
- Uncountable Noun
- The study of the structure of substances
B1Morecollide
US /kəˈlaɪd/
UK /kəˈlaɪd/
- Verb (Transitive/Intransitive)
- To come together or crash with a lot of force
- To disagree with or be very different from others
B1Morecome back
US /kʌm bæk/
UK /kʌm bæk/
- Phrasal Verb
- To reply to someone, often forcefully
- To be remembered
A1Morecompound
US /kɑmˈpaUnd/
UK /'kɒmpaʊnd/
- Noun (Countable/Uncountable)
- Series of buildings that are walled or fenced off
- Chemical made up of several others
- Transitive Verb
- To pay interest on a loan including the interest
- To make something from various parts or components
B1Moreconcern
US /kənˈsɚn/
UK /kənˈsɜ:n/
- Verb (Transitive/Intransitive)
- To be about a particular topic
- To have a direct impact on someone
- Noun (Countable/Uncountable)
- Company, firm or business
- Feeling of worry or anxiety
A2TOEICMorecondensation
US /ˌkɑ:ndenˈseɪʃn/
UK /ˌkɒndenˈseɪʃn/
- Uncountable Noun
- Act of shortening something
- Drops of water on a surface, as produced by steam
B2Moredensity
US /ˈdɛnsɪti/
UK /ˈdensəti/
- Noun (Countable/Uncountable)
- Degree to which an area is filled or covered
- The degree of compactness of a substance.
C1TOEICMoredrift
US /drɪft/
UK /drɪft/
- Intransitive Verb
- (Of sand, etc.) to be blown into heaps by the wind
- (Of boats) to move without purpose on water
B1Moreeffectively
US /ɪˈfɛktɪvli/
UK /ɪˈfektɪvli/
- Adverb
- In a way that produces the desired result
B1Moreend up with
US
UK
- Phrasal Verb
- To have something as a result.
A1Moreequivalent
US /ɪˈkwɪvələnt/
UK /ɪˈkwɪvələnt/
- Adjective
- Equal to something in value, use or meaning
- Having the same meaning or significance.
- Noun
- Thing like another in quality, quantity or degree
B1TOEICMoreester
US
UK
- Noun
- Compound of acid and alcohol with water taken out
C1Morefeature
US /ˈfitʃɚ/
UK /'fi:tʃə(r)/
- Noun (Countable/Uncountable)
- Special report in a magazine or paper
- Distinctive or important point of something
- Transitive Verb
- To highlight or give special importance to
- To give prominence to; to present or promote as a special or important item.
A2TOEICMoreflip
US /flɪp/
UK /flɪp/
- Verb (Transitive/Intransitive)
- To turn your body in the air, as in gymnastics
- To move into a different position quickly
- Noun
- Act of turning your body in the air; somersault
- Movement of something from one position to another
B2Morego ahead
US /ɡo əˈhɛd/
UK /ɡəu əˈhed/
- Phrasal Verb
- To start an activity; start doing, working etc.
- To give permission to do something
- Intransitive Verb
- To start or proceed with something
- To proceed despite potential obstacles or doubts.
A1Moregoing on
US /ˈɡoɪŋ ɑn/
UK /ˈgəʊɪŋ ɔn/
- Phrasal Verb
- To continue doing something
- To happen (usually negative)
A1Morehave to
US /hæv tu/
UK /ˈhæv tə/
- Auxiliary Verb
- Must do
A1Morein order to
US /ɪn ˈɔrdɚ tu/
UK /in ˈɔ:də tu:/
- Preposition
- For the purpose of; with the aim of.
- Phrase
- In a specific sequence or arrangement.
- With the aim of; for the purpose of.
C1Morein terms of
US
UK
- Phrase
- With regard to; concerning a particular aspect.
A1Moreintact
US /ɪn'tækt/
UK /ɪn'tækt/
- Adjective
- Being complete, without damaged or missing parts
B1Moreintermediate
US /ˌɪntɚˈmidiɪt/
UK /ˌɪntəˈmi:diət/
- Adjective
- Between; in the middle; moderate
- Having some knowledge but not advanced
- Noun (Countable/Uncountable)
- Person with some knowledge but not advanced
- Something that comes between two things in time, place, character, etc.
B1Morekick off
US /kɪk ɔf/
UK /kik ɔf/
- Verb (Transitive/Intransitive)
- To start a football match.
- To start a campaign or event.
- Phrasal Verb
- To begin or start something.
- To remove (shoes) by kicking.
A1Moreknow about
US /noʊ əˈbaʊt/
UK /nəʊ əˈbaut/
- Phrasal Verb
- To have information or understanding of a subject or situation.
look at
US /lʊk æt/
UK /luk æt/
- Phrasal Verb
- To use your eyes to focus on something
- To focus your eyes on something carefully
A1Moremagnitude
US /ˈmæɡnɪˌtud, -ˌtjud/
UK /ˈmægnɪtju:d/
- Noun
- Number representing force of an earthquake
- Size or importance
B2Moremechanism
US /ˈmɛkəˌnɪzəm/
UK /'mekənɪzəm/
- Noun (Countable/Uncountable)
- Part of a machine that performs a certain function
- System or process for achieving a certain result
B1Moremess
US /mɛs/
UK /mes/
- Noun (Countable/Uncountable)
- Something that is untidy, dirty or unclean
- A difficult or confused situation.
- Transitive Verb
- To make something untidy or dirty
A2Moremolecule
US /ˈmɑlɪˌkjul/
UK /ˈmɒlɪkju:l/
- Noun
- Two or more atoms chemically combined
B2Moreneutral
US /ˈnu:trəl/
UK /ˈnju:trəl/
- Adjective
- Something with pH value of 7
- Having no positive or negative electrical charge
- Noun (Countable/Uncountable)
- Color that is dull and not bright, such as gray
- The rest position for gears in a car or vehicle
B1Moreoccur
US /əˈkɚ/
UK /əˈkɜ:(r)/
- Intransitive Verb
- To come to pass or to happen
- To be found to exist; to be present.
A2TOEICMoreof itself
US /ʌv ɪtˈself/
UK /əv ɪtˈself/
- other
- Happening automatically without external cause or help.
B1Moreoff the bat
US /ɔf ði bæt/
UK /ɔf ðə bæt/
- Phrase
- Immediately; without delay.
- Referring to the moment a baseball leaves the bat after being hit.
A1Moreon the other hand
US
UK
- Phrase
- Considering a different aspect of the matter; alternatively.
A1Moreopportunity
US /ˌɑpɚˈtunɪti, -ˈtju-/
UK /ˌɒpə'tju:nətɪ/
- Noun (Countable/Uncountable)
- Time, situation when a thing might be done; chance
- A favorable time or occasion for doing something.
A2TOEICMoreover to
US
UK
- Preposition
- Used to hand over to someone else to speak
- The responsibility is now yours
participate
US /pɑ:rˈtɪsɪpeɪt/
UK /pɑ:ˈtɪsɪpeɪt/
- Intransitive Verb
- To take part with others in doing something
- To be involved in a discussion or conversation.
B1TOEICMorepi
US /paɪ/
UK /paɪ/
- Noun
- The ratio of the circumference to the diameter
B2Morepop
US /pɑp/
UK /pɒp/
- Verb (Transitive/Intransitive)
- To cause something to open or burst suddenly
- To go to or in a place for a brief period of time
- Noun (Countable/Uncountable)
- Sweet soda drink
- A short, sharp, explosive sound.
B2Moreportion
US /ˈpɔrʃən, ˈpor-/
UK /'pɔ:ʃn/
- Noun (Countable/Uncountable)
- Serving of food that is intended for one person
- Part of something shared that belongs to a whole
- Transitive Verb
- To separate something to divide among people
B1Morepour
US /pɔr, por/
UK /pɔ:(r)/
- Verb (Transitive/Intransitive)
- To fill a person's glass or cup with a drink
- To make something flow in a steady stream
A2Morepour in
US /pɔr ɪn/
UK /pɔ: in/
- Phrasal Verb
- To arrive or enter a place in large numbers or amounts.
- To add a liquid to something.
A1Morepresence
US /ˈprɛzəns/
UK /ˈprezns/
- Noun
- The same place or area that a person is
- Ability to reach a market, group of people etc.
A2Moreproton
US /ˈproʊtɑ:n/
UK /ˈprəʊtɒn/
- Countable Noun
- Tiny part of atom with positive electrical charge
B2Moreproximity
US /prɑkˈsɪmɪti/
UK /prɒk'sɪmətɪ/
- Uncountable Noun
- State of being near or close to something
B2TOEICMorereact
US /riˈækt/
UK /rɪ'ækt/
- Intransitive Verb
- To change when mixing with other chemicals
- To behave or make a change in a particular way
A2Morereaction
US /riˈækʃən/
UK /rɪ'ækʃn/
- Noun
- Bodily response to a drug or something eaten
- Feeling or action in response to something
A2Moreregular
US /ˈrɛɡjəlɚ/
UK /ˈregjələ(r)/
- Adjective
- Having an equal amount of space or time in between
- Occurring or being done frequently
- Noun (Countable/Uncountable)
- Customers who frequently visit a place
- Soldier who has a permanent job in the army
A2TOEICMorerepresent
US /ˌrɛprɪˈzɛnt/
UK /ˌreprɪ'zent/
- Transitive Verb
- To depict art objects, figures, scenes; to portray
- To show or describe something in a particular way
A2TOEICMoreresonance
US /ˈrɛzənəns/
UK /ˈrezənəns/
- Noun (Countable/Uncountable)
- Continuing to make a loud clear deep sound
- The quality in a sound of being deep, full, and reverberating.
C2Moreresult
US /rɪˈzʌlt/
UK /rɪ'zʌlt/
- Noun
- Something produced through tests or experiments
- Final score of a competition, election or game
- Intransitive Verb
- To be the outcome of other causes and effects
- To happen or exist as a consequence of something.
A2Moreright off the bat
US /raɪt ɔf ðə bæt/
UK /raɪt ɒf ðə bæt/
- other
- Immediately; from the very beginning or start.
B2Morerotate
US /ˈroʊteɪt/
UK /rəʊˈteɪt/
- Verb (Transitive/Intransitive)
- To regularly change people who perform a role
- To regularly change the crops that grow in a field
B2Moresigma
US /'sɪɡmə/
UK /ˈsɪgmə/
- Noun
- 18th letter of the Greek alphabet -
C1Moresolution
US /səˈluʃən/
UK /səˈlu:ʃn/
- Noun (Countable/Uncountable)
- Mix of a liquid and a solid or a gas
- Way to solve or deal with a problem
A2Morespeak of
US /spik ʌv/
UK /spi:k ɔv/
- Phrasal Verb
- To mention someone or something in conversation.
B1Moresubstrate
US /ˈsʌbˌstret/
UK /ˈsʌbstreɪt/
- Noun
- A substance which a catalyst has an effect on
B2Moresymmetric
US /sɪ'metrɪk/
UK /sɪ'metrɪk/
- Adjective
- Having parts that are exactly the same
B2Moreup there
US /ʌp ðɛr/
UK /ʌp ðɛə/
- Adverb
- In or to a higher place or position; far away.
- In heaven.
A1More
Vocabulary
- go ahead: To start an activity; start doing, working etc.
- have to: Must do
- of itself: Happening automatically without external cause or help.
- up there: In or to a higher place or position; far away.
- kick off: To start a football match.
- look at: To use your eyes to focus on something
- off the bat: Immediately; without delay.
- right off the bat: Immediately; from the very beginning or start.
- come back: To reply to someone, often forcefully
- back down: To admit you were wrong; stop claiming
- all along: From the beginning; all the time.
- speak of: To mention someone or something in conversation.
- in terms of
- pour in: To arrive or enter a place in large numbers or amounts.
- in order to: For the purpose of; with the aim of.
- on the other hand : Considering a different aspect of the matter; alternatively.
- as with: In the same way that something happens or is true of something else.
- over to: Used to hand over to someone else to speak
- going on: To continue doing something
- end up with: To have something as a result.
- know about: To have information or understanding of a subject or situation.
- equivalent: Equal to something in value, use or meaning
- opportunity: Time, situation when a thing might be done; chance
- matter: To be of great importance; to count
- presence: The same place or area that a person is
- flip: To turn your body in the air, as in gymnastics
- aware: Knowing or feeling that something exists
- mess: Something that is untidy, dirty or unclean
- position: Person's opinion or attitude about something
- represent: To depict art objects, figures, scenes; to portray
- compound: Series of buildings that are walled or fenced off
- feature: Special report in a magazine or paper
- molecule: Two or more atoms chemically combined
- neutral: Something with pH value of 7
- bit: Device put in a horse's mouth to control it
- bond: Rope, chain or other thing used to tie someone up
- portion: Serving of food that is intended for one person
- mechanism: Part of a machine that performs a certain function
- proximity: State of being near or close to something
- occur: To come to pass or to happen
- regular: Having an equal amount of space or time in between
- concern: To be about a particular topic
- effectively: In a way that produces the desired result
- draw: To attract attention to someone or something
- intact: Being complete, without damaged or missing parts
- form: Sports team or person's current winning record
- reaction: Bodily response to a drug or something eaten
- pour: To fill a person's glass or cup with a drink
- result: Something produced through tests or experiments
- rest: Time when one relaxes, sleeps, or is inactive
- drift: (Of sand, etc.) to be blown into heaps by the wind
- magnitude: Number representing force of an earthquake
- produce: Fresh foods such as fruits and vegetables
- participate: To take part with others in doing something
- solution: Mix of a liquid and a solid or a gas
- intermediate: Between; in the middle; moderate
- react: To change when mixing with other chemicals
- pop: To cause something to open or burst suddenly
- notice: To become aware by sight, touch, or hearing
- lot: What happens to a person in life from chance; fate
- carbon: Chemical element with an atomic number of 6
- order: Religious or social group, as of nuns
- learn: To get knowledge or skills by study or experience
- operate: To control or handle something, such as a machine
- chemistry: The study of the structure of substances
- collide: To come together or crash with a lot of force
- density: Degree to which an area is filled or covered
- step: Movement done as part of a particular dance
- change: To exchange one set of clothes for another
- find: To become aware of something that is happening
- resonance: Continuing to make a loud clear deep sound
- acidic: Containing acid
- arrow: Symbol used on road signs to show direction
- rotate: To regularly change people who perform a role
- condensation: Act of shortening something
- proton: Tiny part of atom with positive electrical charge
- symmetric: Having parts that are exactly the same
- substrate: A substance which a catalyst has an effect on
- beta: Test version of a product or software
- ester: Compound of acid and alcohol with water taken out
- ammonium: A chemical derived from ammonia
- pi: The ratio of the circumference to the diameter
- sigma: 18th letter of the Greek alphabet -
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01:03
She took a brave step forward, leaving behind her comfort zone to chase her dreams.
Vocabulary
- brave
adj. Having courage
- comfort zone
phr. A familiar situation where one feels safe
Explanation
a brave step is a noun phrase, where brave is an adjective modifying the noun step, meaning "a courageous step".
forward is an adverb modifying step, meaning "ahead".
The whole phrase serves as the object, answering the "what" of took (verb) — she took a brave step forward.
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brave
US/brev/
UK/breɪv/
adj.Brave
v.t.To bravely face
A2 Elementary
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Ken Lee posted on 2026/09/29Ever wondered about Claisen condensation? This video breaks down how it works with ester substrates, a key difference from aldol condensation. You'll get a clear look at the mechanism and learn why matching the alkoxide base to the ester's alkoxy group is super important to avoid a messy reaction!
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