重写句子：I have checked my documents several times. I still can’find t the problem.(compound sentence)

重写句子：Not until he crossed the line and felt the tape snap against his chest did Johnson know he had won the race.(loose sentence)

重写句子：Hockey is a sport which is popular in many countries around the world.(simple sentence)

If you _______ in behaving in this way you will bring yourself nothing but trouble.

_______ that the scientist will give us a talk next month?

It makes good ________ to bring an umbrella; it seems to be raining today.

Having decided to rent a flat, we ________ contacting housing agencies in the city.

We are all concerned _______ her safety.

I was really anxious about you. You ______ home without a word.

Very few people understood this contract, ______ was very obscure.