I ______along the street looking for a place to park when the accident______ . 

There is no doubt ________ those who work hard will succeed sooner or later.

Now that their parents are dead, the poor boy doesn’t know ________ the money they left.

Some people are worrying about the possibility ________ mobile phones could be responsible for a range of illnesses, from rashes(皮疹) to brain tumors．

I asked you ________ my dictionary—now I can’t find it.