The shop from 9 a.m. to 9 p.m. But it at 8 pm. on Sundays.A. is open openB. open opensC.

问题补充：

The shop from 9 a.m. to 9 p.m. But it at 8 pm. on Sundays.

A. is open, open

B. open, opens

C. is open, opens

D. is opened, open

答案：

A. is open, open

B. open, opens

(答案→)C. is open, opens

D. is opened, open

解析：open有两个词性，一个是形容词“开着的”，一个是动词“开，打开”。根据题干，本句的意思是“这个商店从上午9点一直开业的晚上9点。”这里的“开业”表示的是一种状态，应该用形容词，故用is open；后本句的意思是“但是它星期天下午8点开门”，此处的“开”是指的动作，故用opens。所以本题选C。