The doctors said it would be months _____ Yao Ming was fit enough for regular training.
No one can be sure in a million years.
____ students are practicing ___ English with each other at the English corner.
My father served in the army in _______ when he was in _____.
Only when finished his own work, ask him to help you.
The reason he missed this class was quite different from the one that you explained to me. A.that B.of which C.why D what