_______ you study harder, you’ll fall behind others.A. If B. Unless C. Until
---It seems that Mr. Wu is standing there. ---It ________ be him because he called me from Canada just now.
---Mr Johnson asked me to remind you of the meeting this afternoon. Don’t forget it!---OK, I _________.
Can you tell me _____?
Please don’t smoke here. The sign _______ “No smoking.”
A smile costs ______, but gives so much.