As a recent survey states, people can hardly enjoy a clear blue sky because of the high level of PM 2.5.
| A．in trouble | B．on purpose | C．as usual | D．in ruins |
Mr Smith gave a notebook away to me. That’s ______ I need badly.
| A．which | B．what | C．why | D．how |
He promised to come early, but he didn’t _____ until 10 p.m.
| A．turn down | B．turn off | C．turn in | D．turn up |
----Would you please be so kind as to close the window?
-----______.
| A．With pleasure | B．Go ahead | C．Yes, please | D．That’s OK |
Some people who don’t like to talk much are not necessarily shy; they _____ just be quiet people.
| A．must | B．may | C．should | D．would |
So sudden _____ that the enemy had no time to escape.
| A．did the attack | B．the attack did | C．was the attack | D．the attack was |