a bag of bones 骨瘦如柴的人

eg. If you don't eat more you'll soon be a bag of bones.
你要再不多吃些，真的要变得骨瘦如柴了。

be skin and bone 瘦得皮包骨；极瘦

eg. He was all skin and bone after his illness.
他病后瘦成了皮包骨。

be as dry as a bone 干燥极了、口渴极了

eg. Let's stop for a drink. I'm as dry as a bone.
咱们停下来喝点什么吧，我的嗓子干得直冒烟。

be bone idle 懒到家了、懒到极点了

eg. The boy has a good enough brain but he's bone idle and won't study.
这个男孩脑子十分好，但就是懒惰成性，不肯学习。

close to the bone 近乎下流的、卑鄙的

eg. Some of his jokes were a bit close to the bone.
他的有些笑话近乎下流。

be chilled to the bone 冻僵了

eg. You will be chilled to the bone without your overcoat.
要是不穿大衣你会感到寒气刺骨。

bone of contention 争论的焦点

eg. The division of their father's property is their bone of contention.
父亲的财产分配问题是他们争吵的原因。

feel in your bones 直觉地意识到，从内心（预）感到

eg. She felt in her bones that she would succeed.
她坚信自己能成功。

bone up 刻苦用功读书

eg. I must bone up on my French before we go to Paris.
在我们去巴黎之前，我必须刻苦学习法语。

throw someone a bone 给某人东西，但并不合乎他的期望

eg. The company gave another man the promotion Bill expected. But they threw him a bone—they sent him out to head a branch office way off in Iowa. And that's a dead-end job nobody wanted.
这家公司把Bill所向往的升迁机会给了别人，然而他们还是给了Bill一点恩赐，但是这并不合乎Bill的期望，他们派Bill去主持远在依阿华州的分部办公室。这是无人问津、一无发展前途的职位。