use the best steel to make the knife's edge - - use material where it is needed most; use the best material at the key point
Related Translations:
刀刃: 1.(刀口) the edge of a knife; cutter edge; knife edge; tool edge; bit; blade point; blade2.(最能发挥作用的地方) where a thing can be put to best use; the crucial point 短语和例子好钢用在刀刃上 use the best steel
