Practice greeting your teacher and classmates in English. Remember !
A. smiling
B. to smile
C. to be smiling
D. having smiled
网友回答
A. smiling
(答案→)B. to smile
C. to be smiling
D. having smiled
解析：考查remeber的用法，remeber to do sth表示记得要做某事；remeber doing sth表示记得做过某事，所以选B