hem and haw
1．pause or hesitate while speaking often with little throat noises哼哼 哈哈的不置可否；哼哈声
He was a poor lecturer because he hemmed and hawed too much．他 不是个好的演讲者，因为他哼哼 哈哈，停顿太多。
2．avoid giving a direct and clear answer避免作正面回答
He hems and haws and comes out on both sides of every question．他 避免作正面回答而对每一问题都 采取模棱两可的态度。