_____ is known to us all is that the old scientist, for _____ life was hard in the past, still works very hard in his eighties.
---I am afraid that I have to trouble you with this question. ---___________.
--How long are you staying ? -- I don’t know . ______.
The Olympic Games are held _____.
This area experienced ____ heaviest rainfall in ____ month of May.
We offered these students a summer course ,aimed _____ improving their spoken English.