The magician often _____ on talent shows. We all know him very well.
句意：那位魔术师经常出现在オ艺表演中，我们都很熟悉他。表示“出现”要用 appear，故答案为选项D。
— What happened to Alice?
— She _____ the horse and broke her leg.
四个选项的含义分别是：pick up 捡起；fall off 从……跌落；take away 带走；lift up 举起。根据本题语境可知，她从马上摔下来，摔断了腿，故答案为选项B。
Jack _____ a shower when his mother rang him up.
本题考査动词时态。
句意：当杰克的妈妈给他打电话的时候，他正在洗淋浴。故要用过去进行时。