BY THE TIME HE ______, ALL HIS CLASSMATES _______A. ARRIVED/ HAD L...

18. - DE KIEM TRA 1TIET BAI SO 2
DE KIEM TRA 1TIET BAI SO 2

18. By the time he ______, all his classmates _______

A. arrived/ had left

B. arrived/ left

C. was arriving/ has left

D. arrives/ feel