We were swimming in the lake _______ suddenly the storm started.
| A．until | B．while | C．when | D．before |
I am very sad that I ______ many chances in the last few years.
| A．miss | B．missed | C．have missed | D．am missing |
—Must we clean the classroom now?
—No ,you _______.
| A．must | B．needn’t | C．aren’t | D．mustn’t |
—____________?
—Very well, thanks.
| A．How are you |
| B．How do you do |
| C．Where are you |
| D．What are you doing |
Scientists can make the robots __________.
| A．to dance | B．dance | C．dancing | D．danced |
You shouldn’t ________ here . The baby _____.
| A．play; sleeping |
| B．to play; is sleeping |
| C．plays; sleeps |
| D．play ; is sleeping |