---Where _______ my book ? I can't see it anywhere. --- I _______ it on this table . But now it's gone . A were you putting ; have put B. had you put ; was putting C have you put ; put D. did you put ; have put
— Have you found your English book? — I am not sure ____ I could have left it.
The art center is ______ used to be Factory 789 and _______ millions of tractors were made.
____ students should be given more free time is suggested by many experts and welcomed by kids in school.
When I try to find ______that prevent so many people from taking part in the program, it seems to me that there are two main causes.
— Will you go to the annual meeting to be held in Sweden from the 26-30th of August 2008? — That depends on _______ I am invited.