Having a trip abroad is certainly good for the old couple,but it remains ______ whether they will enjoy it。 A.to see B.to be seen C.seeing D.seen
答案: B 该题考查非谓语动词的用法。前一个it为形式主语,代替主语从句“weather they will enjoy it”;后一个it指前一个并列分句的主语“Having a trip abroad”。后一个分句的主语是作表语的动词不定式动作的承受者。所以不定式要用被动式。