The fact has worried teachers and parents ________ more and more students have got near-sighted.
____ difficult the work may be, we must go all out to finish it ahead of time.
What worried the child most was ____ to visit his mother in the hospital.
The baby cried again. The young mother felt very ____ and her husband wore ____ expression on his face, too.
There is ____ Mr. Smith at the door who wants to speak to you.
. To make sure that he was at home, I called him up ____ . A. by chance B. in general C. in particular D in advance