Now we are in a position (where) we have to accept that we a

你类比的句子如果改一下,we are at the place where he was born。意思是我们就在他出生的地方。这里的at a place 和元句子的in a position 是一样的都是在句子中作表语,因为在系动词后面。而后面的where引导的定语从句只是修饰前面的先行词,与先行词前面的介词无关。当然,Now we are in a position (where) we have to accept that we are wrong。=Now we are in a position (in which) we have to accept that we are wrong。which 指代的是position。加油