Havingawalkaftersupperiscertainlygoodfortheoldpeople,b...

問題詳情：

 Having a walk after supper is certainly good for the old people, but it remains ______ whether they will enjoy it.

   A. to see                 B. to be seen             C. seeing                D. seen

【回答】

B

知識點：非謂語動詞

題型：選擇題