Short explanation:
Short explanation: This sentence requires the Past Simple affirmative form to describe an action completed last Sunday. The verb 'think' in the past simple is 'thought'.
Step-by-step solution:
- The sentence structure is Subject + Verb + Object/Complement.
- The subject is 'They'.
- The time given is 'last Sunday', indicating the Past Simple tense.
- The verb 'think' in the Past Simple is 'thought'.
- Therefore, the sentence becomes 'They thought about me last Sunday.'
Answer: 4. They thought about me last Sunday.