Question

I have received________to his birthday party．But I haven't decided whether to go．

1. A.
   an invention
2. B.
   an invitation
3. C.
   invitation
4. D.
   event

Answer 1

B
分析：空格词是I have received的宾语，应该是“收到了请帖”的意思，选名词“邀请”，但invitation在此处变成“请帖”的意思，所以前面还有冠词an．