51When they entered the room, they found the windows open and something________.
A.stolen
B.to be stolen
C.to steal
D.stealing
开始考试练习点击查看答案52The research scientists often meet with problems________new types of instruments for solutions.
A.require
B.to require
C.required
D.requiring
开始考试练习点击查看答案53What’s done is done.It’s no use ________ anyone for it.
A.blaming
B.blame
C.to blame
D.to be blaming
开始考试练习点击查看答案54He stopped________ last week and feels much better now.
A.smoking
B.smoked
C.smokes
D.to smoke
开始考试练习点击查看答案55There is no point________to remember all those names and addresses.The most important thing is to understand the events associated with them.
A.to try
B.to be trying
C.trying
D.be trying
开始考试练习点击查看答案56I’m going to get my letters ________up tomorrow afternoon if I can finish writing them today.
A.type
B.to type
C.typed
D.typing
开始考试练习点击查看答案57John suggested________anything about it until they found out more facts.
A.not tosay
B.not say
C.to say not
D.not saying
开始考试练习点击查看答案58________to wait for hours, she brought along a book to read.
A.Expected
B.Expecting
C.Expects
D.To expect
开始考试练习点击查看答案59She is old enough________herself on her own.
A.take care of
B.to take care of
C.taking care
D.to take care
开始考试练习点击查看答案60________from Buckingham Palace, this trip takes you to the best of London’s sights.
A.Beginning
B.Begun
C.To begin
D.Having begun
开始考试练习点击查看答案