问题
There are so many viruses on the Internet. If ______ accidentally, the viruses may make your computer break down.
A:downloading
B:to be downloaded
C:downloaded
D:being downloaded;
B:to be downloaded
C:downloaded
D:being downloaded;
正确答案是：
同类题型
Only after they had discussed the matter for a few hours _______a decision
Did you enjoy yourself at the party? –Yes, I’ve never been to ______one before.
Tom and Mary ______polite．They ______listening to music.
haven’t got the service advertised ontheir website, they you have _____ to complain about it.