You ________ worry about him. He will get well soon.
A. needn’t B. can’t C. mustn’t
—Nancy, would you mind turning down the music? Your father is writing his report. —.
| A．Yes, please | B．Sorry. I’ll do it right away |
| C．Sorry. I won’t do it again | D．Yes. I never do it again |
---You are late again. The class ________ for five minutes.
---Sorry. There is something wrong with my bike.
| A．began | B．has begun | C．was on | D．has been on |
_______ the mouse, you can choose an icon _______ for more details.
| A．By; to click on | B．With; to click on |
| C．With; to click | D．By; to click it |
----Look at the boy running on the playground. Is it David?
---- It ______ be him. I saw him go to the teachers’ office just now.
| A．mustn’t | B．can’t | C．may not | D．needn’t |
---With 4G mobile phones, people can even see each other as they talk.
----Really? Would you show me it, please?
| A．how to use | B．when to use | C．where to use | D．what to use |