英语句子：请教此处to的用法

to 在这里是个一介词,表示“.的” ,
the door to his apartment 意思为他公寓的门.
例：the key to the door 门的钥匙
the answer to the question 问题的答案
the solution to climate change 气候变化的解决办法
the witness to the crime犯罪的目击证人
Jim braced himself aganist the door to his apartment and let nobody came in .
Jim 撑在他公寓的门上,不让任何人进来.