1. see

-> If 1 : If + S1 + Vs/es, S2 + will + Vinf

2. had done

-> After + quá khứ hoàn thành, quá khứ đơn

3. to ride

-> how + to V 

4. scientists ( n : các nhà khoa học, S + be + one of + N số nhiều )

5. will be watching ( at 9pm tomorrow: tương lai tiếp diễn )

6. using ( avoid + Ving )

7. had ( If 2: If + S1 + V2/ed, S2 + would + Vinf )

8. invention ( sự phát minh )

II

1. will be sitting

2. to have

3. announced

4. comfortable 

1, see

2, did

3, to ride

4, scientist

5, will be watching

6, using

7, had

8, inventive

10, will be sitting

11, to have

12, announced

13, confortable

@Xin ctlhn