They have fun ______(listen) to the loud music.xx
问题描述：
They have fun ______(listen) to the loud music.
xx
答
to listen
答
listenning
是have fun doing sth句型
have fun (in) doing sth．开开心心做某事
类似还有have problems（in）doing sth．做某事有困难
problem后接动词－ing形式，其前的介词in可以省略。如：
They had no problem（in）fixing the car．
答
listening
have fun doing sth
答
have fun doing sth. 开心地做某事
答
have fun doing sth.开心地做某事
没有have fun to do sth结构.如：The kids are having fun playing in the park now.
那么就是listening了.