问题补充:
The letter he had been looking forward to at last .
A. arrive
B. arrives
C. arriving
D. arrived
答案:
A. arrive
B. arrives
C. arriving
(答案→)D. arrived
解析: 考查句子结构。此题缺少谓语,he had been looking forward to为定语从句,省略了关系词that/which。句子的主干为:The letter arrived at last.句意:他一直期望的那封信终于到达了。故选D。