shake your arms and your legs的意思是挥舞你的胳膊和你的腿。
shake:动摇 ，摇头，挥动。
例：
1、The nurse shook the thermometer and put it under my armpit.
护士把体温计甩了甩，然后放到了我的腋下。
2、As soon as he got inside, the dog shook himself.
他一进来，狗就开始摇头摆尾。
3、'Anything else?' Colum asked. Kathryn shook her head wearily.
“还有别的吗？”科拉姆问。凯瑟琳疲惫地摇了摇头。
4、He roared with laughter, shaking in his chair.
他放声大笑，笑得身子在椅子上直颤。
5、Another man constantly chain-smoked and seemed to have the shakes.
另一名男子一直一支接一支地抽烟，似乎身体有些发抖。
shake：动摇，摇头，挥动。