:check:如果关系代词是宾语，且为who, which, that则可以省略；
比较：I found the key (that) I had lost.
This is the key that opens the front door.
例：the day I arrived, the year I worked in Egypt.
:check:在somewhere, anywhere, everywhere, nowhere, place后面可省略where
例：somewhere we can get a drink.
例：I never found out the reason (why) she left.
如：I didn't like the way (in which) he spoke to me.