---Can you tell me how often he practices his English?-.A. At timesB. At one timeC. At

问题补充：

---Can you tell me how often he practices his English?

---.

A. At times

B. At one time

C. At all times

D. At a time

答案：

(答案→)A. At times

B. At one time

C. At all times

D. At a time

解析：考查介词短语：A. At times有时，B. At one time曾经，一度，C. At all times一直，D. At a time一次，句意：--你能告诉我他多长时间练一次英语吗？--有时。选A。