Question

Not until he had left his friend _______ how important friendship was for him.

1. A.
   did he realize
2. B.
   he realized
3. C.
   had he realized
4. D.
   he had realized

Answer 1

A
試題分析： 1.當Not until位于句首時,句子要倒裝。其結構為:Not until+從句/表時間的詞+助動詞+(主句)主語+謂語+...。故排除BD，realize發生在had left 之后，故用一般過去時。 ②Not until next week will the sports meet be held.直到下周才開運動會。
考點：部分倒裝。
點評：當Not until位于句首時,句子要倒裝。
即學即練： It ______ we had stayed together for a couple of weeks ______ I found we had a lot in common.
A. was until; when B. was until; that C. wasn’t until; when D. wasn’t until; that
選D