I wonder ____ we can solve this hard problem.
They _____ building the new hotel because of the great cost.
-Excuse me! How can I get to the nearest post office?-Walk along this road for a few minutes. and you will___.
---Your accent is great. You sound like an American native.--- ________. I still have trouble expressing myself.
Jim took this course, _________ improve his spoken English.
You had better drink this , for it _______ vitamin C and it is good to your health.