--I can’t solve the math problem because it is too difficult. What should I do? -- _________ ask the teacher for help?
—It’s a wise________to wear the white tie.It matches your shin well.—Thank you very much.
The bad weather has________their projeet.
—Have you finished your work?—No,not yet.I think it’ll take________two hours.
What will happen if he________to the party?
They never work hard because they haven’t known the________of study.