Mark the letter A, B, C or D to indicate the correct answer to each of the following questions.

Câu hỏi

We usually watch videos _____________ smartphones and the Internet.

A. in

B. at

C. on

D. to

Đáp án
C. on

Câu hỏi thuộc Bài tập:

E6- GS- Unit 10: Test for unit