After he was knocked down by a bike he was badly hurt and had to to his feet. A. standB.

问题补充：

After he was knocked down by a bike, he was badly hurt and had to to his feet.

A. stand

B. struggle

C. run

D. sit

答案：

A. stand

(答案→)B. struggle

C. run

D. sit

解析：本题的含义是他被自行车撞倒之后，他伤的厉害，必须要挣扎着站起来，struggle表示挣扎的意思，故本题选B。