syntactic analysis - Parallel structure with a negative

Would this sentence follow the rules of parallel structure?

In order to improve your country, you should take care of the environment, avoid throwing litter, help society, and don't use plastic.

I could make this sentence better by changing the last part to "avoid using plastic", but I was wondering if the above sentence is correct in its original form.

Answer

Here is the parallel structure at work:

✘ In order to improve your country, you should take care of the environment, ^{you should} avoid throwing litter, ^{you should} help society, and ^{you should} don't use plastic.

Assuming you want to maintain a parallel structure, the sentence is incorrect because of this:

✘ You should don't use plastic.

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However you rephrase the final list item, it should be in a manner that makes it grammatical with a you should ___ plastic structure.

Your own suggestion would be fine. As would some others:

✔ You should avoid using plastic.
✔ You should stop using plastic.
✔ You should not use plastic.