this time betty must work hard_____English.该咋么填?
问题描述：
this time betty must work hard_____English.该咋么填?
用in,at,on,for.
答
work on用作表示花费精力做某事
this time betty must work hard_____English.该咋么填?
用in,at,on,for.
work on用作表示花费精力做某事