She has cooked dinner for two hours.

A. to work                

B. working           

C. being working    

D. to be work

A. having             

B. having had          

C. to have            

D. for having

A. had installed      

B. had been installed

C. had been installing

D. installed

B. aspect              

C. event                

D. affair

A. activity      

B. happy              

D. birthday

A. Because he is old, he can run far.       

B. He is too old to run so far

C. He is old enough to run far.                       

D. Although he is old, he can run far.