"You could scratch your back with it and never draw blood" nghĩa là gì?

"You could scratch your back with it and never draw blood" = có thể dùng để gãi lưng mà vẫn không bị chảy máu -> nghĩa là dao rất cùn.

Ví dụ

With a dull knife, you can't cut anything even soft foods. You could scratch your back with it and never draw blood.

Sharp knives in the kitchen are very important. With a dull knife, you're forced to exert more pressure and you could scratch your back with it and never draw blood.

Are you sick of using dull knives all the time and can't find the right one? Thankfully, now you know what you want. You could scratch your back with it and never draw blood.

Bài trước: "You could ride all the way to Big Spring on it and never split a hair" nghĩa là gì?