733.Please tell me the after-service of the computer,I'm worried about ________ a breakdown sometime.
A.there being
B.it being
C.there is
D.it is
734.Many teachers strongly object to _______ at school.
A.smoke
B.smoking
C.smoked
D.having smoked
733.答案是A;考查非谓语动词；worry about后接动名词。
734.答案是B;object to doing反对做某事。
