I think the breakage of that that door causes by: first, students who inadvertent break it. probably when they're playing with the door until the door is break and they don't care so that the door can't be locked. second, probably the age of the door has already been old and the key is loose so the door can't be locked. third, the school is less responsive to repair the broken door, so that until now the door can't be locked. in order that the door can be locked like before, the school should repair those broken doors in order to prevent something unwanted. and students also don't play with the door that cause the door is broke and can't be locked.