All the class keep quiet _________ the class begins.
| A．until | B．since |
| C．as soon as | D．though |
I often go to sleep ________10:00 p.m. ________7:00 a.m.．
| A．at, at | B．at, and | C．between, and | D．from, to |
—Could you pass me the book?
—______________.
| A．OK. Here you are. | B．Let me think. | C．Yes, I could. | D．No. |
Most students hope _______well in their study.
| A．doing | B．do | C．to do | D．does |
Half of the books ________easy for the students to read．
| A．are | B．is | C．am | D．be |
The cat climbs into the sitting-room _______the open window．
| A．through | B．across | C．cross | D．over |