Did

[jack]

He did not become a millionaire.
He did not became a millionaire.

Why is became wrong?

[Susie Smith]

He did not become a millionaire.
He did not became a millionaire.

Why is became wrong?

To make the simple past negative, we put did not (didn't) before the infinitive (without to).

He saw the man. He did not see the man.
He went to school. He did not go to school.
He wrote a letter. He did not write a letter.
He had a good time. He didn't have a good time.

[MikeNewYork]

He did not become a millionaire.
He did not became a millionaire.

Why is became wrong?

The verb "do" (past tense = did) is used as an auxiliary verb there; it is used with another verb in its base/infinitive form. When we place "do/does become" into the past tense, we change "do/does" to "did". We don't change "become" to "became". :wink: