同义句Li Lei often played football,but now he does not.

Li Lei used to play football,(but now he doesn't.)
后半句可省略,因为used to do sth.(过去常做……),本身就隐含现在的情况相反.
---绝对没错!

Li Lei used to play football．
或
Li Lei often liked to play football．

Li Lei used to play football.
used to曾经

li lei used to like playing football.