— How long do you suppose it is ______ he arrived here?— No more than half a week.
We've been told the good news, but when and where to go for theexciting paid vacation __________ yet.
In 1948,three American scientists invented __________ transistor, which is __________ small electronic device to control an electric current.
__________ yesterday, we went out for a walk.
Peter is a brilliant language learner. Within two weeks, he hasdeveloped a good __________ of Chinese and Japanese. A. custom B. imaginationC. exception D command
—How do you know our team will win the race in the final?— __________ We are well prepared for it and do more practice aswell.