can ever be用法
我们来看两个句子
- can the magnitude of the instantaneous velocity of an object ever be greater than the magnitude of its average velocity?
- can it always be greater?
这里can ... ever be是疑问句，表示经验性询问。即，是否存在这种可能，是否可能存在某一刻瞬时速度大于平均速度
always表示一直，整个过程中瞬时速度一直大于平均速度
我在这里吐槽下自己，居然误解can ever be为一直，瞬时速度一直大于平均速度。
面壁思过。。。
ever 用法
根据doctionary.cambridge.org的解释
every，adverb，意思是at any time
疑问句例句:
表达存在可能性
- has he ever scored a goal before? 他之前是否进过球（表达存在性，并不要求一直进球，只是是否进过）
- do you ever dream about winning the lottery? 你是否梦见过中彩票（表达存在性，是否做过中彩票的梦）
- have you ever heard the Ivy restaurant? 你是否听说过Ivy餐厅(表达存在性，听过一次也是听过)
否定句
表示从来没有
我们可以在否定句中使用not ... ever，但是更常见的情况是我们会用never
- Tom doesn't ever call me at weekends. 或者 Tom never calls me at weekends.
- We haven't ever had a problem with noise in the neighborhood before. 或者We have never had a problem with noise in the neighborhood
否定句中与no one, nobody, hardly联用
- No one ever told me what had happened
- We have hardly ever eaten Vietnamese food. (我们几乎没有吃过越南菜)
if .. ever用法
表示假设条件
-
if ever you move house, I'd advise you to get a good removal company. (如果你搬家，我建议你找个好点的搬家公司)
-
if you ever go to Washington, make sure to visit the Art Gallery.
-
If you are ever in Winnipeg, we should get together and have a party.
ever so和ever such
表示强调语气
- I feel ever so cold. 我【TMD】（这里不是在叫大家说脏话，只是强调一下语气）好冷啊
- He was ever such a kind man. 他【TMD】（这里不是在叫大家说脏话，只是强调一下语气）曾经是个很好的人
ever since用法
我们在since前面加上ever来强调从某一刻起某一事实成立
- ever since we met, we have been such great friends. 从我们见面那天起，我们就已经是很好的朋友了
- Mrs Tom doesn't go for walks on her own ever since she fell. 自从摔倒之后，Tom就再也不独自去散步了。
as .... as ever用法
表示比较
- it's as busy as ever. 和往常一样忙
- They've built a new road around the city but traffic is as bad as ever. 他们在城市周围修了一条新路，但是交通还是和过往一样的差
ever表达always
在非常正式的场合，ever联用形容词可以表达always的意思
- the company cannot sustain ever-decreasing profits. 公司无法在一直亏损的情况下支撑下去
- Tom was ever available to help the family. Tom一直有空去帮助邻居
一些说不清楚的情况，lol，毕竟现有语言后有语法
- happily ever after. 这里ever就表达always
参考
https://dictionary.cambridge.org/grammar/british-grammar/ever?tdsourcetag=s_pcqq_aiomsg
linguistics专业大神的指导
