Do you know the reason ____ he was late?

Einstein won the Nobel Prize in 1921 and enjoyed great fame in Germany until the rise of Nazism ____ he was expelled from Germany because he was a Jew.

As the pressure____, the liquid rock is forced up through channels in the resistant rock to the earth’s surface.

Last Friday I saw some boys ______ behind Daniel, _____ the computer games.

I hope you will spend as much time as you can ________ your English.

—I came to your office yesterday morning, but nobody was in.

—Oh, we__________ a meeting in the meeting room.

Tom has been a vegetarian ____principle for years .

Last night he saw two dark _____ enter the building, and then there was the explosion.

____the center of our planetary system was considered as heresy by the church in the Middle Ages.

Tammy: Someone is at the doctor.

Richard: ______.