Ex 2 : Cho dạng đúng của động từ trong ngoặc.
1. By the time you arrive, I (write)………… the essay.
2. By this time tomorrow they (visit)………… Paris.
3. By the time he intends to get to the airport, the plane (take)…………. off.
4. By the year 2012 many people (lose)……….. their jobs.
5. I know by the time they come to my house this evening, I (go)……… out for a walk.
6. I hope they (finish) ……..building the road by the time we come back next summer.
7. By 2020, the number of schools in our country (double)…………..