Children do not use inflections such as are used in mature adult speech.

儿童不使用像成年人言语中使用的那些词形变化。

《柯林斯英汉双解大词典》

When you get past a certain age, as a mature adult, you want to be treated as an adult.

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In animal experiments, such transplants mature into adult nerve cells and insinuate themselves into the damaged cord, restoring at least some movement to an otherwise paralysed body.

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There will be plenty of time for love and respect when the child grows into a mature and responsible adult.

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