--- Have you ever been to Tibet?--- Yes. I ____________ there three times in the year 2008.
To their disappointment, they found the lecture given by the professor difficult__________.
As soon as he heard the ________ news of his death, she _______ tears.
----I’m going to the United States. ---- How long ____you ____in the States ?
He often helps the students _________he thinks are not quick at their studies.
This painting of his had been ____________ by some experts of the world.