He lives in a flat, ________ he can see ________ is happening in the street．

A．where; which

B．from the window of which; that

C．where; that

D．from whose window; what

________ two exams to worry about, I have to work really hard this weekend．

A．With

B．Besides

C．As for

D．Because of

________ such heavy pollution already, it may now be too late to clean up the river．

A．Having suffered

B．Suffering

C．To suffer

D．Suffered

A large number of people attended the celebration, ________．

A．include our teacher

B．our teacher includes

C．our teacher including

D．our teacher included

Just as the value of a telephone network increases with each new phone ________ to the system, so does the value of a computer system increase with each program that turns out．

A．adding

B．to have added

C．to add

D．added