问题补充:
We take this opportunity to express our sincere of your timely help.
A. anxiety
B. ambition
C. association
D. appreciation
答案:
A. anxiety
B. ambition
C. association
(答案→)D. appreciation
解析:句意,我们利用这次机会,对于你及时的帮助,表达我们真诚的感谢。Anxiety焦虑 ambition抱负 association联合 appreciation感谢,根据题意,故选D。