问题补充:
We set off early next morning and came to unknown valley after about an hour.
A. the; the
B. the; an
C. /; a
D. /; the
答案:
A. the; the
(答案→)B. the; an
C. /; a
D. /; the
解析:考查冠词。句意我们第二天造成早早地出发了,在大约一小时后到了一个不知名的山谷。结合语境可知前文特指某个早晨,下文泛指任何一个不知名的山谷,故选B。