20. ______ entering the concert hall, I noticed that refreshments were being served.
(A) On
(B) About
(C) To
(D) Of
詳解 (共 3 筆)
未解鎖
On/Upon +ving… ,S +過...
未解鎖
on / upon + Ving:一…就...
未解鎖
On entering the conc...
私人筆記 (共 2 筆)
未解鎖
On entering the conc...
未解鎖
正確答案:(A) On 解析: 句意:...