问题补充:
My brother to the ground while his bicycle and hurt his leg .
Afalls; is he riding
Bfell; he was riding
Cfall; he is riding
Dfelt; was he riding
答案:
A. falls; is he riding
(答案→)B. fell; he was riding
C. fall; he is riding
D. felt; was he riding
解析:句意:我哥哥骑自行车时摔到地上摔伤了腿。while后跟过去进行时,此处主句用过去时,fall的过去式是fell,故选B。