问题补充:
Because the shop, all the T-shirts are sold at half price.
A. has closed down
B. closed down
C. is closing down
D. had closed down
答案:
A. has closed down
B. closed down
(答案→)C. is closing down
D. had closed down
解析:考查时态。根据后半句:T恤半价出售,说明这家店还没有关门,只是即将关门。故C正确,现在进行时表示将来时。