Once we discover a mistake, we should not ______ it but correct it immediately, to create better conditions for economic development.  

We will wait for further information, you should keep us_________.

Students living far away from home will be happy with our dormitories, all of which ____ its own bathroom.

------ You don’t look well. Are you ill?
------ No, the exam is coming, and I _____ reading until midnight.

The school to which David ______ his paintings is beautiful.

Though it was noisy here, he _______reading.

Yesterday I _______ an old friend of mine at the shopping mall.

—Do famous athletes and entertainers        such high salaries?
—Well, at least I think scientists should be paid more．

His first concert was well ____ and so all the tickets of his second one were sold out quickly.

His mother insisted that high school education ________ very important and insisted that Bob ________ it.