Once harm ______ to the environment, it takes years to have the system recovered.
| A．does | B．is done | C．will be done | D．be done |
The fire spread through the hotel very quickly but everyone _______ get out.
| A．had to | B．would | C．could | D．was able to |
—When can I come for the photos？ I need them tomorrow afternoon．
—They _______ be ready by 1200.
| A．can | B．should | C．might | D．need |
—Will you stay for lunch?
—Sorry, _______.My brother is coming to see me.
| A．I mustn't | B．I can't | C．I needn't | D．I won't |
Johnny, you _______play with the knife, you _______hurt yourself.
| A．won't; can't | B．mustn't; may |
| C．shouldn't; must | D．can't; shouldn't |
I should have been there, but I _______ not find the time.
| A．would | B．could | C．might | D．should |