阿摩線上測驗
19. It is hard to ______ between these two similar plants.
(A) differ
(B) different
(C) differentiate
(D) difference
答案：登入後查看
統計： A(1), B(0), C(5), D(0), E(0) #3257511
統計： A(1), B(0), C(5), D(0), E(0) #3257511
