6. His wife ____ dinner yesterday.

Grammar Rule:

In the past simple tense, negative sentences are formed using 'did not' (or 'didn't') followed by the base form of the verb. For example: 'He did not go', 'She didn't eat'.

Analysis:

The sentence is in the past simple tense, indicated by 'yesterday'. We need to form a negative statement. The correct structure is 'did not' + base verb.

• Option a: 'didn't cooked' - Incorrect because 'cooked' is the past participle, not the base form.
• Option b: 'didn't cook' - Correct. 'didn't' is the auxiliary verb, and 'cook' is the base form.
• Option c: 'did not cooked' - Incorrect. 'did not' is correct, but 'cooked' is the past participle, not the base form.

Ответ: b. didn't cook