i'm quite at a loss to guess

i'm quite at a loss to guess who can it be i am quite at a loss to guess. I'm completely at a loss I'm really at a loss! I'm at a loss as to what to do and feel lost there are five pairs ___,but I'm at a loss which to buy. There are five pairs___, but I'm at a loss which to buy. 答案是 1.There are five pairs ______,but I'm at a loss which to buy I’m completely at a loss the know what to do next,what shoul 1、There are five pairs ____,but I'm at a loss which to buy. 不定式做定语There are five pairs ______,but I’m at a loss which to 这是啥意思?英译中I'm at a loss as to what you mean by saying so!