Rút gọn các phân số sau

a)  11.8 − 11.3 17 − 6

b)  24 − 12.13 12 + 4.9

Rút gọn các phân số sau:

a ) 33 66 ; b ) − 22 77 ; c ) 3030 6060 .

Rút gọn các phân số sau:

a)  3 6 ;

b)  30 60 ;

c)  − 5 15 .

My friend ___________________  for 4 hours before he arrives.

A. will be driving

B. had driven

C. will have been driven

D. will have been driving

After my husband ___________________ his work, he went straight home.

A. would finish 

B. has finished 

C. had finished 

D. was finishing