while 语句用来实现当型循环，其一般形式为：
while（表达式）
语句；
“表达式”为循环条件，“语句”为循环体。
while语句含义：判断循环条件也就是“表达式”，如果为“真”，就执行循环体。

[QUOTE]while
[(h)wail]
n.
一会儿, 时间
conj.
当...的时候, 虽然
vt.
消磨
prep.
<古><方>直到
while
while
AHD:[hwºl, wºl]
D.J.[hwa!l, wa!l]
K.K.[hwa!l, wa!l]
n.（名词）
A period of time:
一段时间：
stay for a while; sang all the while.See Usage Note at awhile
停留下会儿；一直都在唱歌参见 awhile
The time, effort, or trouble taken in doing something:
费时：做一件事情的花费时间、努力或工夫：
The project wasn't worth my while.
这项方案不值得我花工夫，
conj.（连接词）
As long as; during the time that:
只要；在…时间里：
It was lovely while it lasted.
当它开着的时间它是很惹人喜爱的
At the same time that; although:
在…同时；尽管，虽然：
While the grandparents love the children, they are strict with them.
“虽然祖父母们都爱他们的孩子，但却对他们要求严格”
Whereas; and:
然而；而，而且：
The soles are leather, while the uppers are canvas.
鞋跟是皮的，而鞋面是帆布的，
v.tr.（及物动词）
whiled,whil.ing,whiles
To spend (time) idly or pleasantly:
消磨：闲散或轻松地消磨时间：
while the hours away.
消磨时光
Middle English
中古英语
from Old English hwºl * see k wei…-
源自 古英语 hwºl *参见 k wei…-
while
[(h)wail]
n.
时间; 一段时间, 一会儿
Wait a while.
等一会儿。
It took a long while to do the work.
做这个工作花了许多时间。
What have you been doing all this while?
这一阵子你一直在做什么?
while
[(h)wail]
conj.
当...的时候, 和...同时; 只要
但是, 然而
虽然; 尽管
half-turn while in hanging
悬垂转体180°
Write while I dictate.
当我口述时请你记下。
Some people like coffee, while others like te
adj.
有些人喜欢咖啡, 而有些人喜欢茶。
While he loves his students, he is very strict with them.
虽然他爱他的学生, 可是他对他们很严格。
prep.
[古]到...时候止, 直到...
vt.
消磨, 闲混(时间)(away)
a good [long, great] while
长[许]久
a little while
不久, 一会儿
a while ago
方才, 刚才
after a while
不久, 过一会儿
all the while
始终, 一直
at whiles
有时, 时常
between whiles
间或, 时或
every little while (=at whiles)
有时, 时常
for a [one] while
暂时
in a little while
不久, 没一会儿
make it worth sb.'s while
酬谢某人, 贿赂某人
the while [whilst]
(与此)同时, 在此期间
while you are about it
[口]顺便, 在你做这个的同时
worth (one's) while
值得的; 值得花费时间, 值得一干; 有益的
while
while
AHD:[hwºl, wºl]
D.J.[hwa!l, wa!l]
K.K.[hwa!l, wa!l]
n.
A period of time:
stay for a while; sang all the while.See Usage Note at awhile
The time, effort, or trouble taken in doing something:
The project wasn't worth my while.
conj.
As long as; during the time that:
It was lovely while it lasted.
At the same time that; although:
While the grandparents love the children, they are strict with them.
Whereas; and:
The soles are leather, while the uppers are canvas.
v.tr.
whiled,whil.ing,whiles
To spend (time) idly or pleasantly:
while the hours away.
Middle English
from Old English hwºl * see k wei…-
while
来自古英语 hwil[/QUOTE]

英语，我永远的痛啊！~