The problem is so complex that I'm afraid it will take me several hours to________.
—— Do young people in that country like to be engaged in teaching? —— Not really, for teachers strongly feel that school systems____ them ____.
I wonder how it ________ that they made such rapid progress.
Readers can ___ very smoothly without knowing the exact meaning of each word.
The nurse treated the naughty boy very kindly, but her patience ____ at last.
The boss _____ 30 dollars from my salary without any good reason.