When the old man_____to walk back to his house,the sun____itself behind the mountain.
The generation _____ makes it difficult for parents to understand their children's opinions.
With sufficient scientific information a manned trip to Mars should be _____.
_____ inviting guests and not treating them properly!
_____ it is a good thing I did not get the post I had applied for, though I must admit that I was disappointed at the time.
Maria _____ missed the first train so as to travel on the same one as John.