—What'sthematter,Jack?   —I   downwhileI

問題詳情：

—What's the matter,Jack?

    —I    down while I____on the ice. I got hurt badly.

   A. was falling, skated     , was skating

  , skated                  falling, was skating

【回答】

B

知識點：動詞和動詞短語

題型：選擇題