Sure, here are the sentences with the verbs in the correct form of the present simple tense:

1. Our math lesson usually **finishes** at 4.00 p.m.
2. The reason why Susan **does not eat** meat is that she **is** a vegetarian.
3. People in Ho Chi Minh City **are** very friendly and they **smile** a lot.
4. The flight **starts** at 6 a.m. every Thursday.
5. Peter **does not study** very hard; he never gets high scores.
6. I like oranges and she **likes** apples.
7. My mom and my sister **cook** lunch every day.
8. They **have** breakfast together every morning.