1.leg指动物或人的“腿”,是可数名词;指“腿肉”时,既可用作可数名词,也可用作不可数名词。leg有时指“(一段)旅程”或“(一个运动项目的)赛程”,是新闻用语。
2.说“腿瘸”时不可用leg作主语,而应以人作主语。

be all legs
过分瘦长 be disproportionately long and thin
You are all legs.What do you have every day?你长得又瘦又高,你每天都吃些啥?

be on one's legs
1.站着 be standing, especially to make a speech
 I' ve been on my legs all day and I'm tired out.我整天站着,累极了。
2.康复至可以走动 after an illness be well enough to walk about
It was the first time she was on her legs after her illness.这是她病后第一次起来走动。

give sb a leg up
1.帮助某人上马或爬墙等 help sb mount a horse, climb a wall, etc.
I can climb in this window if someone gives me a leg up.如果有人助我一臂之力,我能爬进这窗口。
2.用钱或影响力帮助人 use money or influence to help sb
It was a good opportunity for them to give their candidate a leg up.这对他们来说,是帮助他们的候选人克服困难的好机会。

not have a leg to stand on
(论点等)站不住脚,对行为无合理的解释等 have nothing to support one's opinion, justify one's action, etc.
 He hasn't a leg to stand on for his behaviour.他的行为是完全没有道理的。
She hasn't got a leg to stand on if she's forgotten to write, because I reminded her every day for a week.如果她忘了写,就没有道理,因为我每天提醒她有一个星期了。

pull one's leg
开某人的完笑,耍弄某人 make fun of sb, especially by making him believe sth that is untrue;tease sb
You're pulling my leg,I haven't really got a big spider crawling up my back, have I?别开我的玩笑了,哪儿真有一只大蜘蛛爬在我的背上。
They have just been pulling our legs.他们是跟我们开玩笑。

shake a leg
出发,动手,赶快 get moving;start to act;hurry
Shake a leg!We won't get back before dark if we don't hurry.快,如果不抓紧,我们在天黑前赶不回来。

show a leg
起床 get out of bed
Show a leg!It's time you were all up and about—breakfast is in five minutes' time.醒醒!你们都该起来了——五分钟后用早餐。

stand on one's legs
自食其力 make a living for oneself
Father has warned me that I must stand on my own legs after leaving school.父亲已经告诉我了,中学毕业以后必须自立。

stretch one's legs
去散步 go for a walk as exercise
I've been sitting at this desk for over five hours,I think I'll just go outside and stretch my legs.我坐在这张桌子旁已5个多小时了,我想该出去散散步了。

walk off sb's leg
把某人累得筋疲力尽 tire sb by making him walk too far or too fast
▲walk sb off sb's leg
I took the children to the zoo and they walked me off my legs.我带着孩子们去了动物园,他们让我走得疲惫不堪。

Humans have two legs, dogs have four.人有两条腿,狗有四条腿。
He felt an intense pain in his leg.他感到腿部疼得厉害。
He lost the use of his legs.他双腿残疾。
His legs refused to carry him further.他的腿已不听使唤,一步也走不动了。
Would you like some leg or some breast of turkey.你要火鸡的腿肉还是胸肉?
She bought a leg of mutton.她买了条羊腿。
The leg of my tights has torn.我的连裤袜的裤腿破了。
He lost his left leg in the war.他在战争中失去了左腿。
Most chairs have four legs.大多数椅子是四条腿。
The last leg of our trip was most tiring.我们旅行的最后一段行程最累人。
From Bombay we made a long leg to Singapore.我们从孟买到新加坡的一段旅程很长。
The premier has just completed the first leg of his five-nation tour.这位总理刚刚结束了他五国之行的第一段旅程。

leg有时也可用作动词表示“步行”。例如:
It's no use, the car won't start, we'll have to leg it.没用的,汽车发动不起来,我们只好走路去。

［同义词］   brace, gam, lap, limp, member, part, pin, portion, prop, section, stage, support
［词源］  ＜古英语leggr(腿)