left与remain的用法区别都当剩余剩下讲时

remain 比left比较正式

left跟主语不在一个地方
remain是
这么理解好点

remain
To continue in the same state or condition:
保持不变继续保持同一种状态或情况：
These matters remain in doubt.
这些事情仍然值得怀疑
To continue to be in the same place; stay or stay behind:
留下逗留在同一地方；停留或者留下：
We are remaining at home.
我们留在家里
To be left after the removal, loss, passage, or destruction of others:
余留在其他事物移走，丢失，走开或毁坏之后仍留下来：
Only a few trees remain.
只留下了一些树
See: stay1
To be left as still to be dealt with:
尚待剩余的仍需要处理的：
A cure remains to be found.
尚待发现的疗法
To endure or persist.
持久或坚持
leave
v.tr.
To go out of or away from:
离开从…走出或远离：
not allowed to leave the room.
不准离开房间
To go without taking or removing:
留下没有拿走或移走：
left my book on the bus.
把我的书留在公共汽车上了
To omit or exclude:
舍去省略或排除：
left out the funniest part of the story.
省略了故事中最有趣的部分
To have as a result, consequence, or remainder:
成…的结果作为结果、后果或遗迹而拥有：
The car left a trail of exhaust fumes. Two from eight leaves six.
车子留下废气的痕迹；八减二得六
To cause or allow to be or remain in a specified state:
维持使或允许在或保持某一特定状态：
left the lights on.
让灯亮着
To have remaining after death:
遗留死后保留有：
left a young son.
死后留下一个年幼的儿子
To bequeath:
遗赠：
left her money to charity.
她把钱遗赠给慈善机构
To give over to another to control or act on:
交付，托付转交给另外的人让他控制或采取行动：
Leave all the details to us.
将细节都交给我们
To abandon or forsake:
放弃，抛弃：
leave home; left her husband.
抛弃家庭；离开她的丈夫
To remove oneself from association with or participation in:
脱离使自己避免与…的联系或参与：
left the navy for civilian life.
脱离海军恢复平民生活
To give or deposit, as for use or information, upon one's departure or in one's absence:
留下某人离开或不在时给予或存放以备使用或告知某事：
He left a note for you. Leave your name and address.
他给你留了封短信。留下你的姓名和地址
To cause or permit to be or remain attainable:
允许使或允许得到或保持得到：
left myself plenty of time.
给自己充裕的时间
leave是实意动词
表示动作

vt. 将...留在...
What a pity I left it at home.
真糟糕，我把它忘在家里了。
remain [ ri'mein ]
v. 保持,依然,剩余,留下，逗留
n.遗迹，剩余物，残骸
Words fly, writings remain.
言语飞逝，著作长存。

当leave 意思为剩下的时候,是及物动词,而 remain不是.