WE WON’T EAT UNTIL……….AREA IS CLEAN .A. AT ALL B.THE WHOLE C.COMPL...

71. We won’t eat until……….area is clean .

A. at all

B.the whole

C.complete

D.of all

72…………..Huansui, why do people use the internet ?

A.According

B. According to

C.To

D.Folloiwng to