The letter I____hasn't arrived yet

问题描述:

The letter I____hasn't arrived yet
A was looking foeward to
B am looking forward
C haved been looked forward
D have been looking forward to

D
现在完成进行时,表示我从过去开始盼这封信,一直持续到现在,并且可能还将继续盼下去.
因为这封信还没到嘛!