for jet engines and auxiliary power units.

This sentence follows normal word order. Subject + auxiliary verb + adverb + verb.

First, move the negative adverb to the beginning of the sentence. Then, invert or swap the order of the subject and auxiliary verb.  

Trick question - there was an auxiliary verb 'has' and a main verb 'hated' and 'always' went after the auxiliary verb. Rule number three.

Now we can also use the verb have as an auxiliary verb and we use it to form the present perfect and present perfect continuous tense.

Have a look at this sentence here, "I have gone to that show already." Here, we can see the verb have is being used as the auxiliary verb.

An APU, or auxiliary power unit, is a small motor

because it's used without an auxiliary verb. So let's compare to the correct standard English

that I do this one, especially in text messages and things like that. No auxiliary verbs when

or that auxiliary DNA can actually give them a new trait, like the ability to be virulent

highly desirable. However, this is not enough. Those are just auxiliary, help conditions.

For the regular verbs we use the auxiliary verb to have and a past participle.

we also use the auxiliary verb to have and a past participle

You mean between regular, irregular and auxiliary verbs?

Ah ... and the three auxiliary verbs, to be, to do, and to have are essential in life.