Mark the letter A, B, C, or D on your answer sheet to indicate the word or phrase that is CLOSEST in meaning to the underlined part in each of the following questions.
On completion of the activities you will have to continue answering some questions.
A. Completing of the activities
B. When you have completed the activities
C. Because you complete the activities
D. As if you completed the activities
Đáp án là B. On + V-ing = When + S + V ( đồng chủ ngữ với vế sau)