don't know/can't tell etc which is whichLIKE/SIMILARif you do not know which is which, you cannot see the difference between two very similar people or things 不知道/分不清哪个是哪个 The twins are so alike I can never tell which is which. 这对双胞胎长得如此相像,我怎么也分不清哪个是哪个。
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