1. Lan was excited because that was the first time she travelled by plane

S + V + because + S + V: bởi vì

QKĐ: S + V2/ed + O

2. We immediately set off for the cinema when Paul arrived

S + V + when + S + V: khi

QKĐ: S + V2/ed + O

3. By the time Ben arrived, I had finished all my work

By the time + S + V2/ed, S + had + VpII + O

4. After we had walked for 3 hours, we reached the top of the hill

After + S + had + VpII, S + V2/ed + O

5. Before sitting on the chair, Mary had made a sandwich

Before + V-ing + O, S + had + VpII + O

=> Rút gọn "before" khi cùng chủ ngữ

6. After having had a good meal, they went to dance

After + V-ing + O, S + had + VpII + O

=> Rút gọn "after" khi cùng chủ ngữ

7. After having done his homework, he went to bed

After + V-ing + O, S + had + VpII + O

=> Rút gọn "after" khi cùng chủ ngữ

8. He drove to into the park and then he walked to the office