Infantile in a sentence and paraphrased in a sentence.

Here are examples of the word/phrase "infantile" used in a sentence and paraphrased in a sentence...

I couldn't take him seriously because his attitude was infantile.

I couldn't take him seriously because his attitude was childish.

That boy used to be goofy and infantile, but now he is serious and mature.

That boy used to be goofy and juvenile, but now he is serious and mature.

The way she carried herself at the party the other day was very infantile.

The way she carried herself at the party the other day was very childish.

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