.As is _______ known, a good knowledge of basic physics helps us better understand natural phynomenons.
Considering the coming of the entrance exam,some schools have abandoned the ______of doing morning exercises.
The teacher told the monitor to ______ all the students' names who were absent from class.
John may phone tonight,I don't want to go out ______ he phones.
He is always helping people without expecting anything ______.
I will mark ______ everything you say.It is helpful to the English learners.