Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions
It is the high time John understands how to behave properly towards the old men
A. understands
B. high
C. towards
D. how to
A
It + is + (about) (high) time + S + V-ed = đã đến lúc ai đó phải gấp rút làm gì. A -> understood