10. Why do the baby crying?

Mistake Correction:

The original sentence is 'Why do the baby crying?'

1. Mistake: The auxiliary verb 'do' is incorrect for the third-person singular subject 'baby' when forming a question in the present continuous tense. Also, the main verb 'crying' is in the correct form for present continuous, but the auxiliary verb is wrong.
2. Correction: The correct auxiliary verb for the third-person singular subject 'baby' in the present continuous tense is 'is'. The word order should be 'Why is the baby crying?'.

Corrected sentence: Why is the baby crying?