Now people can with their friends far away by e–mail, cellphone or letter.A. keep on B. keep in touch C. keep up
---How many Chinese astronauts ______ into space since 2003? ----Twelve , including two women.
---Who helped you clean the classroom yesterday? ---_______. I did it all by myself.
I remember ______ the math problem ______.But I can’t remember it’s answer.
It’s said that _____ of the water around the world _____ polluted.
---May I have a look at your plan for the robot ? ----Sorry ,I’ve _____ it at home .