Recognising broad categories of images is one of the general problems that computers are not______.
The truth in question is that success in life depends chiefly on sustained efforts _________ (这种努力来源于对所选职业的一种深厚的兴趣).
What was the worker doing when the accident happened? He______the inside of the tower.
______(请务必做到) no children should lean out of the window.
It was the first time he (finish) __ his composition in 25 minutes.
Wewereallsurprisedthat______(他独自一人自愿承担起这一艰巨的任务).