Subtitles section Play video Print subtitles Hey there, and welcome back. In this lesson, we're going to learn all about simple, compound and complex sentences. Many of you have asked me to do a lesson on this topic, so here we are. Now, in this video, I'll show you the differences between these three types of sentences, and there are exercises within the lesson for you to practice what you learn. So, let's begin. So, what is a simple sentence? A simple sentence is just a sentence that contains a subject and a verb. For example, I am a teacher. Here, the subject is “I” and the verb is “am.” Here's another one: She took a cab to the airport. Can you identify the subject and the verb here? The subject is “she” and the verb is “took.” One more example: We're having pizza for dinner tonight. In this sentence, the subject is “we,” and the verb is actually the phrase “are having.” It has two words: first, the auxiliary or the helping verb “are” and then the main verb “having,” but still, “are having” is a phrase that acts as a single verb. So, in all of these sentences you see that they have a subject and a verb, so these are simple sentences. Now, there's another name for a simple sentence, and that is an independent clause. This means more or less the same thing as a simple sentence, but just remember that it's another name for a simple sentence. So, what's a compound sentence then? Well, a compound sentence is just a sentence that has two independent clauses. We saw that a simple sentence has just one clause, but a compound sentence has two (or sometimes more) independent clauses. Take a look at this example: I am a teacher. My wife is a lawyer. What we have here is two separate independent clauses or simple sentences, and the problem with this is that it sounds choppy and disconnected when we say it like that: I am a teacher. My wife is a lawyer. Instead, we can combine them like this: I am a teacher, and my wife is a lawyer. This sounds much better, and now we have one compound sentence with the two independent clauses connected by the conjunction “and.” Here's another example: She tried to lift the suitcase. The suitcase was too heavy. We can combine these clauses using “but”: She tried to lift the suitcase, but it was too heavy. Notice that we have the word “it” in the second part. Now, “it” is a pronoun that just refers to the suitcase. It makes the sentence sound better by avoiding repetition. Next example: He didn't have enough cash. He paid by credit card. We can connect these clauses using “so”: He didn't have enough cash, so he paid by credit card. One last example: We can take a bus to the museum. We can just walk there. What we see here is two options; two different ways to get to the museum. We can connect these using “or”: We can take a bus to the museum, or we can just walk there. Now, the connecting words that you see in these examples, “and,” “but,” “so,” “or,” etc. These words are called coordinating conjunctions. That's a fancy word, but it just means that these are connecting words that connect two independent clauses. And there's another important point here: you see that in all of the examples, when we connect the two independent clauses, we put a comma after the first clause. Now, this is the proper form: you write the first independent clause, then you put a comma after it, and then a conjunction, and then you write the second clause. Remember this rule. OK, we're going to practice this now. You see five items on the screen. In each one, I want you to combine the simple sentences into one compound sentence. Use a coordinating conjunction like “and,” “but,” “or,” or “so” to make the compound sentence. Stop the video now, try the exercise, and then play the video again and check. OK, let's discuss them. Number one: She dropped her phone on the floor, and it broke. Number two: I'm not very hungry, so I'll just have an orange juice. Three: You should study harder, or you'll fail the exam. Four: We'd like to buy a car, but we can't afford one right now. And number five is a little tricky because there are three simple sentences or three independent clauses. But we can connect them using coordinating conjunctions. I told my roommate to turn down the TV, but he didn't, so I got up and left. How many did you get right? Alright, let's now move on and talk about complex sentences. Here's a clause first: When I got home from work yesterday. What do you notice about it? Well, it has a subject “I” and a verb “got,” but this clause is just not a complete sentence. And that's because if I say to you, “When I got home from work,” yesterday you will ask, “OK, what happened? What did you do? So, you see this thought is not complete, so this is not an independent clause. This type of clause is called a dependent clause. To make it a complete sentence, you have to add an independent clause. For example, When I got home from work yesterday, I watched TV for an hour. So, you see that there is a dependent clause and an independent clause, and now it's a complete sentence. And this type of sentence is called a complex sentence. Here are some more examples, but before I talk about them, in each one, I want you to identify the dependent clause and the independent clause. Stop the video and try the exercise, then play the video again and continue. Alright, in number two, “I love to travel” is the independent clause and “because I get to meet a lot of interesting people” is the dependent clause. Now, in sentence number one, we saw that the dependent clause came first, and here in number two, the dependent clause comes second. That's OK. In complex sentences, you can put the clauses in any order; that's no problem. Alright, number three: “Even though the exam was quite difficult” is the dependent clause, and “All the students passed” is the independent clause. And number four: “Let me know” is independent, and “if you need any help” is dependent. And finally, number five: “You can't go out and play” is the independent clause, and “until you finish your homework” is the dependent clause. Just remember that to decide whether a clause is dependent or independent, you ask the question, “Can this clause be a complete sentence on its own?” If it can be a complete sentence, then it's an independent clause, and if it cannot be a complete sentence, then it's a dependent clause. Now in all of these examples, you see that the dependent clauses start with a linking word like “when,” “because,” “even though,” “if,” and “until.” These words are conjunctions, but they're called subordinating conjunctions. The dependent clauses are also called subordinate clauses; it means the same thing, so the conjunctions are subordinating conjunctions. If you remember from the previous section, we connected the independent clauses using coordinating conjunctions, and here we're using subordinating conjunctions. Now, there's one more thing I want you to notice here, and that is the use of commas. In sentences 1 & 3, you see that there is a comma, but in sentences 2, 4 & 5 there's no comma. And this is because in 1 & 3, the dependent clause comes first. If the dependent clause comes first, we put a comma after it, and then we write the independent clause. But in 2, 4 & 5, an independent clause comes first. If that's the case, we don't put a comma after it. Now, if you want to learn more about punctuation and about the proper use of commas, I have a separate lesson just on that topic. It's called punctuation masterclass; I will leave a link in the description. You can go and check it out. There's another type of dependent clause that you need to know about, and that is the relative clause. A relative clause uses a relative pronoun like “who,” “that,” “which,” etc. For example, I know a guy who plays guitar in a rock band. This sentence is actually a combination of two sentences: I know a guy, and He plays guitar in a rock band. Both of those are simple sentences, and we combine them using the relative pronoun “who.” So, “who plays guitar in a rock band” is a relative clause that gives us information about the guy. It tells you who that guy is. But, that clause is not a complete sentence, and so, it's a dependent clause. And the entire sentence is a complex sentence. Here's another example: Synonyms are words that have similar meanings. Here, “that have similar meanings” is the relative clause. And one last example: The boss wants me to give a speech at the event, which is tomorrow. Here, “which is tomorrow” is the relative clause. Now, I'm not going to go into detail on relative clauses here because they're a big topic, and we'll have to explore them in a different lesson. But for now, just remember that relative clauses can also be part of a complex sentence. OK, I have another exercise for you. You see six items on the screen. In each one, I want you to combine the simple sentences into one complex sentence. Use the word in the parentheses to do this. Stop the video now, try the exercise, then play the video again and continue. Now, there are different ways to rewrite each sentence. I'll give you my answers. Here's how I wrote the first one: People eat a lot of fast food nowadays even though they know it's bad for their health. Number two: You can't borrow any books from the library unless you have a membership. Number three: She couldn't log in to her Gmail account because she had forgotten her password. Four: Harvey was a vegetarian until he married Susie. Now, this sentence is much shorter than the original two sentences, but it has the same meaning. Number five: The man who lives in that house is a millionaire. And finally, number six: Children shouldn't be allowed to play video games that contain violence.