It was through Xiao Li ____ I got to know Xiao Wang.

It was not until she came to see us ____ her mother was ill in bed.

It was not until 1920 ____ regular radio broadcast began.

It was about 600 years ago ____ the first clock with a face and an hour hand was made.

____ is a fact that English is being accepted as an international language.

He said, “ ____ a long way to school. ____ a long way to go yet before we arrive.”

It ____ Mike and Mary who helped the old man several days ago.

Was it in the place ____ the last emperor died?

It was simply for that reason ____ I wouldn’t tell him the truth.

Hurry up! ____ getting darker and darker.