Of all the subjects,I like _________ history best because it gives us_________useful knowledge of things in the past.
| A．the;a | B．/;a | C．a;the | D．a;/ |
The bus ____ at six, but it arrived an hour later.
| A．should arrive | B．had arrived |
| C．should have arrived | D．must arrive |
The hotel ____ me ＄50 for a single room during one night.
| A．took | B．cost | C．charged | D．paid |
Little ______ that we were watching his every move，so he seemed to be going his own way in this business.
| A．did he know | B．he didn't know | C．didn't he know | D．he knew |
When the woman was told that her husband had a car accident, her mind _____.
| A．ended up | B．made sense | C．blocked out | D．went blank |
Color-blind people often find it difficult to _____ between blue and green.
| A．compare | B．separate | C．distinguish | D．divide |