4.50 adding 'do'

If there is no other auxiliary verb, you put 'do', 'does', or 'did' after the subject, followed by 'not' or '-n't', followed by the base form of the main verb.

• They do not need to talk.
• He does not speak English very well.
• I didn't know that.

'Be' and 'have' are exceptions to this; this is explained in the following paragraphs 4.51 and 4.52. The shortening of 'not' to '-n't' is explained in paragraphs 4.55 and 4.56.