by now 的用法The experts were now fully convinced that the animal was a puma .这句话中NOW ,事情发生在过去,.After acrossing the Equator ,the caption called in at a portto have a now rudder fitted.but by now the Thermopylae was over fiveh

by now 的用法The experts were now fully convinced that the animal was a puma .这句话中NOW ,事情发生在过去,.After acrossing the Equator ,the caption called in at a portto have a now rudder fitted.but by now the Thermopylae was over fiveh
by now 的用法
The experts were now fully convinced that the animal was a puma .这句话中NOW ,事情发生在过去,.After acrossing the Equator ,the caption called in at a port
to have a now rudder fitted.but by now the Thermopylae was over fivehundred miles ahead .上面句子中的by now 一样,我不是很明白过去时态中也有用到NOW 的用法,

by now 的用法The experts were now fully convinced that the animal was a puma .这句话中NOW ,事情发生在过去,.After acrossing the Equator ,the caption called in at a portto have a now rudder fitted.but by now the Thermopylae was over fiveh
by now
到如今
now
[nau]
adv.
现在,目前,此刻; 直到现在
立刻,马上
[叙述中表示可涉及的时间]于是,然后; 那时
[表示感情或语气,如请求、命令、安慰、警告等]哎,呀; 那么; 哟; 喂
Write to him now.
马上写信给他.
Now ,listen to me.
那么,听我说.
You don't mean it,now.
这话不会是当真的吧?
He was now a boy only.
那时他只是一个孩子.
now
conj.
既然; 由于
Now (that) you are grown up,you should not rely on your parents.
既然你长大了,就不应该依靠你的父母.
Now(that) he is well again,he can go on with his English study.
既然恢复了健康,他就可以继续学习英语.
adj.
现在的,当今的; 现任的
属于新一代的
[亦作Now ][俚]非常时髦的; 熟谙最新时尚和潮流的
the now chairman of the association
现任的协会主席
Now Generation
"新一代"人
now
n.
[常用在介词后]现在,此刻
read the future in the now
从现在推测未来
Now is the right time for harvesting.
现在正是收割季节.
He should have arrived by now.
此时他该到了.
nowness
n.
现在性
before now
以前
but now
[古](=just now)
by now
这时(已),至此
ere now
[古、诗]在这以前
even now
即使如此,尽管这样
now and then (=every once in a while)
不时,时而,偶而
now and again (=every once in a while)
不时,时而,偶而
every now and then (=every once in a while)
不时,时而,偶而
every now and again (=every once in a while)
不时,时而,偶而
for now
[口]暂时,目前,眼下
from now on
从现在起,今后
how now
[古](莎士比亚著作中常用) 喂!哎!
怎么样,身体怎么样!
just now
刚才,方才; 眼下,现在
now,now
[口](用于安慰等)好啦,好啦
now ...now ...
时而...时而...; 忽而...忽而
now ...then ...
时而...时而...; 忽而...忽而
now ...again ...
时而...时而...; 忽而...忽而
...
(now wind,now rain 一会儿刮风,一会儿下雨)
Now (in the time) or never!
机不可失,时不再来!
now that
(连词)既然,由于
now then
[口]看呵; 那末,得啦
Oh,come now!
嗨,得啦!
Really now!(=Now Really!)
嗳呀!真的吗!
till now
到现在为止,迄今
until now
到现在为止,迄今
up to now
到现在为止,迄今
Well,now!
[口]唷!喂!好吧!