换句话说，胳膊或者腿 fall asleep，其实就是你身体这些部位失去感觉的状况，也就是你的胳膊或腿感觉麻木或刺痛。有时人们也将这种感觉描述为如坐针毡。
英语中对这种“麻”的感觉，也有一个词来表达：
numb
unable to feel anything in a particular part of your body especially as a result of cold or anesthesia
身体的某一特定部位失去知觉，没有任何感觉，
尤指由于寒冷或麻醉
My legs are numb.
也有一个更地道的表达
I can't feel my legs.
我感觉不到我的腿（我的腿麻了）。
类似的，
I can't feel my tongue.
我的舌头麻了。
除了腿麻之外，
我们也经常会遇到腿抽筋的情况，
“抽筋”英文表达为
cramp
抽筋
Jim always has a cramp in his leg.
吉姆经常腿抽筋。
I got a cramp in the leg when I played basketball this morning.
我今天早上打篮球的时候腿抽筋了。
表示某部位“抽筋”时，要用介词in，如“腿抽筋”是have a cramp in the leg，“脚抽筋”是have a cramp in the foot。
也常见表达成
Charley horse
The term first arose in the 1880s, from the American sport of baseball. One story states that the term was first used to describe a lame horse named Charley that pulled the roller at the White Sox ballpark in Chicago. A second origin theory gives the credit to a baseball pitcher of the 1880s named Charley Radbourne, also known as Old Hoss, who suffered a muscle cramp during a baseball game.
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