Tìm lỗi sai và sửa lại

Ex : My teacher advised me study hard for the next semester 
                         study -> to study 
1. I wish I can go to see all the wonders which have been recognized by UNESCO 
                  ............ -> ..............
2. Tom said that he is learning English in an evening  class then 
                 ........... -> .............
3. If we use fewer paper , we can save trees in the forest 
                 ............ -> .............
4. Na ofter finish her homework before she goes to bed 
                ............. -> .............