1. Why is he scared?

⇒ Because he hates the sound of the drill.

2. Why do the children often have toothache?

⇒ Because they eat lots of candy.

3. Why were you late for class yesterday?

Because I missed the first bus.

4. Why does her tooth hurt?

⇒ Because it has a cavity.

5. Why didn't they come to the meeting last night?

⇒ Because they were busy.

6, Why does she go to the doctor?

⇒ Because she has a headache.

7. Why didn't Minh say anything yesterday?

⇒ Because he was very nervous.

8. Why do you brush your teeth after meals?

⇒ Because we want to have healthy teeth.