He has worked the maths problem for nearly an hour but he simply can’t work it .On ;at B. on ;out C. at ;up D. for ;out
________ help the people in the snowstorm in the South made him worried.
The position, however, _______ you are applying, is not quite a well-paid one.
–Why, Simon. Someone seems to have called you over there. --Yes? I _______ that.
Though Jack has failed twice in _____ PE test, he decided to have _____ third try.
With the world changing fast, we have something new _____ with all by ourselves every day.