Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the underlined partthat needs correction in each of the following questions.
For injection to be effective on tetanus, it must be administered within 72 hours of the injury.
A. to be
B. on
C. administered
D. hours
For injection to be effective on tetanus, it must be administered within 72 hours of the injury.
A. to be
B. on
C. administered
D. hours
in - effective đi với giới từ in
Đáp án B.