1. A serious road accident happened while we were waiting for the bus yesterday. (while)

S+ Ved/cột 2+ while+ S+ was/were+ Ving?

2. I had to get the mop since I spilled my juice

because/as/since+ clause: bởi vì

3. He fell down the ladder and his leg was broken.

S+ Vqkđ+ adnd+ S+ Vqkđ

4. We had picked up trash before leaving the campsite

S+ had P2+ before+ Ving

5. It started raining when they were putting up the tent.

hđ đang diễn ra có 1 hđ khác xen vào=> qktd: S+ was/were+ Ving

9. When it rains, my father usually drives me to school.

• A serious road accident happened while we were waiting for the bus yesterday.
• I had to get the mop since I spilled my juice.
• He fell down the ladder, and his leg was broken.
• We had picked up trash before we left the campsite.
• It started raining when they were putting up the tent.
• I will go out with my friends after I get my parents' permission.
• The weather was bad when we were on holiday last month.
• I will call my mom as soon as I get the result.
• It rains when my father usually drives me to school.
• Jack can't play games before he finishes his homework.