561.The ability _____ an idea is as important as the idea itself.
A.expressing
B.expressed
C.to express
D.to be expressed
562.The island,______ to the mainland by a bridge,is easy to go to.
A.joining
B.to join
C.joined
D.having joined
561.答案是C;考查非谓语动词作定语的用法。Ability作为一个抽象名词，其后通常接动词不定式作定语。
562.答案是C;island与join之间为被动关系，故应选过去分词；而joined to the mainland by a bridge作定语，相当于定语从句which was joined to the mainland by a bridge.
