问题补充：
doesn’t seem to have been much difficulty in solving the problem.
A. It
B. That
C. There
D. He
答案：
A. It
B. That
(答案→)C. There
D. He
解析：这是There be句型一种比较复杂的表现形式，由下列各句逐步形成：
There is much difficulty in solving the problem.
There seems to be much difficulty in solving the problem.
There seems to have been much difficulty in solving the problem.
There doesn’t seem to have been much difficulty in solving the problem.
E.g. There used to be a big tree in front of the old house.
There happened to be a foreign teacher there.
There is said to be no life on the moon.
There must have been something wrong with the machine.
