Question

2.The film (be) very confusing. You(understand) what (go) on?

3.Poor David! He (study) History for five hours when he (realize) that next day's exam (be) Science.
4.Quick! Look at the timetable. What time the next plane (leave)? 

Answer 1

Is,do you understand,what is going on,had been studying ,realized ,was,what time is the next plane leaving