(一)原因
1.A number of factors are accountable for this situation.
A number of factors might contribute to (lead to )(account for) the phenomenon (problem).
answer to this problem involves many factors.
phenomenon mainly stems from the fact that...
factors that contribute to this situation include...
change in ely results from the fact that...
may blame ...,but the real causes are...
of the explanations for it is that ...
One of the most common factors (causes that ...
Another contributing factor (cause ...
Perhaps the primary factor is that …
But the fundamental cause is that
(二)比较
advantage far outweigh the disadvantages.
advantages of A are much greater than those of B.
3.A may be preferable to B, but A suffers from the disadvantages that...
is reasonable to maintain that it would be foolish to claim that...
all the disadvantages, it has its compensating advantages.
anything else, it has its faults.
7.A and B has several points in common.
8.A bears some resemblances to B.
ver, the same is not applicable to B.
10.A and B differ in several ways.
ently, it has both negative and positive effects.
le used to think ..., but things are different now.
same is true of B.
ering as A is, it has its drawbacks.
is true that A ..., but the chief faults (obvious defects )are ...
