closed, shut, locked 和 private 的区别：怎么用更自然
closed = 没打开或不营业；shut = 关上了，常用于门、窗、眼睛、嘴；locked = 上锁了；private = 仅限本人或特定人群，不对外开放。
closed 侧重“没打开/不运行”；shut 侧重“把东西关上”；locked 侧重“用锁、密码或钥匙锁住”；private 侧重“对外人不可见或不可进入”。
现在该用哪个词
如何选择单词
当你只是想说“没开着”或“不营业”时用 closed，比如商店、办公室、道路。
当你要强调把门、窗、眼睛、嘴巴或盖子“关上”时用 shut。
当你想表达“被锁住了，没钥匙/密码打不开”时用 locked。
当你想说“不是给公众看的/用的”时用 private，比如账号、信息、会议。
逐词说明
closed
closed = 只是“没开/不开放”，不一定有锁。
The store is closed on Sundays.
The store is closed on Sundays.
The road is closed because of the accident.
The road is closed because of the accident.
如果强调“锁住了”，不能只说 closed；要说 locked。
把 closed 理解成“状态上没有打开”。
shut
shut = 通过动作把东西关上，常比 closed 更有“动作感”。
Please keep the door shut while the baby is sleeping.
Please keep the door shut while the baby is sleeping.
She shut her eyes and tried to relax.
She shut her eyes and tried to relax.
不要把 shut 乱用到“账户”“文件权限”这类场景；这些通常要看是否 private 或 locked。
想到“啪地关上”或“把眼睛闭上”，就常是 shut。
locked
locked = 关上 + 上锁；重点在“不能随便打开”。
The door is locked, so we need the key.
The door is locked, so we need the key.
I left my phone in the car, and the car is locked.
I left my phone in the car, and the car is locked.
别把 locked 简单换成 closed；如果要钥匙、密码或解锁，必须用 locked。
locked 里最关键的是“lock”，先想到锁，再想到关闭。
private
private = 不是“关没关”，而是“给谁看/谁能进”的问题。
Her Instagram account is private.
Her Instagram account is private.
This is a private meeting; only team members can join.
This is a private meeting; only team members can join.
“私密账号”应说 private account，不是 closed account；closed account 另有“已关闭账户”的意思。
private 直接联想到“只给自己人”。
常见错误
中文里“关闭/关上/封闭”常被一律译成 closed，但英语里要看具体含义：上锁要用 locked，私密账号要用 private，不一定都能用 closed。
记忆提示
先判断是哪一种“关”：只是没打开用 closed；手动关上用 shut；有锁、密码或钥匙用 locked；只给自己或少数人看用 private。
