问题补充：
---- the door, please.
----Come in please. The door .
A. Be open; opens
B. Be open; is opening
C. Open; opens
D. Open; is open
答案：
A. Be open; opens
B. Be open; is opening
C. Open; opens
(答案→)D. Open; is open
解析：原句意思是：——请开门。——请进，门是开着的。Open具有动词和形容词两个词性，从原句看，前面的open是动词，表示动作，后面的是形容词，表示状态。故选D。
