Question

He likes pears. (negative sentence) ¡æ

He is the third person singular, so you should put doesn't before the base form of the verb like. Then you can change the affirmative sentence into the negative sentence as follws.
He doesn't like pears. Remember that you should use the base verb 'like' after 'don't' or 'doesn't'.

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Is my explanation above grammatical? Are there any wrong uses of articles? I'd like you to check the expressions above.

Answer 1

<i>He</i> is the third person singular, so you should put <i>doesn't</i> before the base form of the verb <i>like</i>. Then you can change the affirmative sentence into the negative sentence as <b>follows:</b>
<i>He doesn't like pears.</i>
Remember that you should use the base verb <i>like</i> after <i>don't</i> or <i>doesn't</i>.

I corrected spelling and punctuation in bold.

When you are referring to a word or phrase or sentence as a word, not a grammatical part of the sentence, you should use italics (or underlining if you're writing by hand):
http://grammar.ccc.commnet.edu/grammar/italics.htm

Your use of articles is fine.

=)