Each time he opens his mouth, he … something foolish.

Analyze the question The sentence is: "Each time he opens his mouth, he _ something foolish." We need the verb form that fits grammatically.

Explain the concept: subject-verb agreement and tense consistency

• The sentence describes a habitual action, something that happens repeatedly. This calls for the simple present tense.
• The first clause, "he opens his mouth", is in the simple present, so the second clause must match it.
• The subject "he" is third person singular, so the present tense verb takes -s: he says.

Step-by-step solution

1. Identify the subject: he (third person singular).
2. Identify the tense in the first clause: "opens" is simple present.
3. The second clause must also be simple present, with the singular -s ending.
4. Test each option: • A. says: correct, "he says something foolish" is simple present and agrees with "he". • B. saying: a participle that cannot stand alone as the main verb here. • C. said: past tense, which clashes with "opens". • D. say: a plural or base form, which does not agree with "he".

Answer: A. says

Exam tip: In "each time / every time / whenever" sentences, both clauses usually take the same tense. If one verb is in the present with "he/she/it", the other will also be in the present with -s/-es. Always check the subject first, then the tense.