while they are old enough
问题描述：
while they are old enough
while 可以这样用吗?
换成when是不是更好?
答
后半句（前后文）是什么?能写上来吗?
When 只有这一种意思,While 有两种用法,意思完全不一样.
WHEN:
When they are old enough,their parents will let them go.
当他们年纪够大的时候,爸妈就会让他们去了.
When= "当...的时候"
WHILE 1:
While I was watching TV,Julia came in.
我正在看电视的时候,Julia 就进来了.
这一句里面的While = "正在...的时候" (when 指一个时间点,while 指一段时间)
WHILE 2:
While they are old enough,they are not wise enough.
他们虽然年纪够大了,但却不够明智.
这一句里面While= "虽然 (+暗示後半句的"但是"、"却")"