摸著石頭過河 [ㄇㄛ ˙ㄓㄜ ㄕˊ ˙ㄊㄡ ㄍㄨㄛˋ ㄏㄜˊ; mo1 zhe5 shi2 tou5 guo4 he2] to wade the river by groping for stones (idiom) to advance step by step to feel one's way around ◄ ►