In our class ,when the bell rang and the teacher closed his book ,it was a ________for everyone to stand up .
| A．signal | B．chance | C．mark | D．measure |
-What's up? You look worried.
Well,I_____on the problem for 5 hours but I haven't got a single clue.
| A．have worked | B．worked |
| C．will work | D．have been working |
A book I read last year,_______name l can't remember, changed my idea about time.
| A．which | B．that | C．whose | D．what |
l'm afraid that I can't attend Tom's wedding party_______next weekend.
| A．to be held | B．being held | C．held | D．is to be held |
-May I have_____break, mum?
Did you have_____ short one an hour ago?
| A．the; the | B．a;/ | C．the;／ | D．a;a |
You can never be_____careful ; the road is icy and slippery.
| A．very | B．too | C．quite | D．rather |