21. In recent years _____ global warming is becoming ____concern for people all over the world.
| A．the; the | B．/; a | C．/; / | D．the; / |
I feel it a great honor ______ to give a speech here.
| A．to be asked | B．to have asked | C．being asked | D．to ask |
This is the first time that your parents have been abroad, ______?
| A．haven’t they | B．hasn’t it | C．aren’t they | D．isn’t it |
Large quantities of time ______ for practising guided writings.
| A．was needed | B．are needed | C．needs | D．is needed |
The kid is crying, for he ______ jump over the ditch on his own.
| A．dares not to | B．dare not to | C．doesn’t dare to | D．dares not |
I have two sisters but ______ of us are likely to win the scholarship this term.
| A．no one | B．none | C．neither | D．both |