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

Câu hỏi

One of the best forms of exercise is _because it uses a lot of muscles without them.

A. swimming/straining

B. to swim /straining

C. swimming / having strained

D. swimming / to be strained

Đáp án
A. swimming/straining

Câu hỏi thuộc Bài tập:

One of the best forms of exercise is _____because it uses a lot of muscles without____ them.