—What do you feel ______ you are looking through the old pictures?
—How time flies!
句意：——你翻看这些旧照片时有什么感觉？——时间过得真快啊！
考查连词辨析。because因为；though尽管；while当……时候；unless除非。根据答句“How time flies!”感慨时间过得快，可推出是问看旧照片时的感觉，用while引导时间状语从句。故选C。
—What do you feel ______ you are looking through the old pictures?
—How time flies!
We will make fewer mistakes _______ we are careful enough.
— Which do you prefer, tea or coffee?
— Either. ________ tea ________ coffee are my favorite.
Work hard, _________ you will get good grades.
—Excuse me. Where is the nearest hotel?
—Just go down this road ________ you see a library. It’s across from it.
President Xi encourages all Chinese people to plant trees______ our country can be greener and more beautiful.
It was great in the end ______ we had a terrible time at the beginning.
—Peter, would you like to go shopping with me?
—I'd love to, ________ I have to finish my homework first.
In Chinese families, people won't start dinner ________ the elders take their seats.
Swimming is, of course, interesting. But ______ we plan to go swimming, being safe must come first.
