(A) Although he had worked hard/(B) and was
understanding as much about the subject/(C) as I
did/(D) he failed to get a second class in the
examination./(E) No error
Answers
1. A; arrived should come in place of arrived. Because we use the third form of the main verb with has/have/had
2. C; had wanted should come in place of wanted.
3. C; which he had wanted should come in place of he wanted.
4. B; understood should come in place of was understanding because we have "had" in the sentence in part A.
5. A; She told me should come in place of "She has told me" because we are talking about past tense in which the person told us something.
6. C; Spent should come in place of spend because the other part of the sentence is in past tense.
7. D; I have been adopting should come in place od I have adopted to show the continuity of the activity.
8. D; He retires should be used because we use simple present tense to show fixed programs or the plans of nearest future.
9. B; Had begun will come in the sentence because the action was accomplished.
10. D; was a rush should be used because the sentence is in past tense.