The invention of steam engine greatly sped up the industrial revolution, which _____ a lot to the take-off of the world.
Tom’s mother often requires that hemore time in studying English every day.
We can't go out,for it is getting dark and,it is raining.
Don't put your books everywhere.Keep them.
— I ____ to your birthday party last Sunday. — Unfortunately, you were out on business.
________ in a recent science competition, the three students were awarded scholarships totaling $ 21, 000.