He was so deep in thought，thinking of the problem ________ he knocked into the tree without noticing it.
| A．when |
| B．while |
| C．because |
| D．that |
People in China don’t like hugging each other when meeting, which _________ a common __________ in some European countries.
| A．are, practice | B．is; exercise | C．are; exercise | D．is; practice |
___________, the northerners are fond of dumplings while the southerners are fond of rice.
| A．In common | B．In total | C．In general | D．In particular |
Not ______ openly may make one’s point confusing, while careless words are ______ to hurt others’ feelings.
| A．to speak, possible | B．speak, probable | C．speaking, likely | D．spoken, sure |
--- Some more wine?
--- Thank you. __________. I have to drive home.
| A．With pleasure | B．That would be nice | C．I’d rather not | D．Just what I need |
I _________ an old photo while __________ my album, which reminded me of my happy childhood.
| A．came across, looking through | B．came about, looking up |
| C．came along, looking down upon | D．came up with, looking into |