could + 动词原形 (过去能力)
He could run fast when he was young.
can的条件式
conditional of can
情态动词 could 没有 -ing 形式或过去分词，也不使用普通的第三人称单数 -s 变化。
I could read before I started school.
我上学前就会阅读了。
用法提示：could 表示过去具备的能力。
Could you speak a little more slowly?
你可以说得稍微慢一点吗？
用法提示：Could you...? 用于委婉地提出请求。
The delay could cause more problems.
这次延误可能会引发更多问题。
用法提示：could 表示一种不确定的可能性。
He could run fast when he was young.
他年轻时能跑得很快。
用 could 比 can 更委婉礼貌。
Could you help me with this box?
你能帮我搬这个箱子吗？
It could rain later.
待会可能下雨。
grammar · medium
易错句子I could swim very fast now.
正确表达I can swim very fast now.
could 表示过去的能力或委婉语气，不能用于陈述现在的能力，现在能力应用 can。
grammar · medium
易错句子If I had more time, I would go to the party.
正确表达If I had more time, I could go to the party.
在虚拟条件句中，would 表示意愿，could 表示可能性或能力；这里表示‘可能去’，应使用 could。
可能是
It could be a mistake.
这可能是个错误。
本来可以
I could have helped you.
我本来可以帮你的。
不能；无法
I could not believe my eyes.
我无法相信自己的眼睛。
你能……吗
Could you open the window?
你能打开窗户吗？
我可以……吗
Could I have your name?
我可以知道你的名字吗？
它可能
Could it be true?
这可能是真的吗？
毫不在乎
He couldn't care less about the rules.
他对规则毫不在乎。
需要；想要
I could do with a cup of coffee.
我需要一杯咖啡。
我敢发誓
I could have sworn I locked the door.
我敢发誓我锁了门。
我本可以是一个竞争者。
In the film 'On the Waterfront', Terry Malloy laments his wasted potential, saying, 'I could have been a contender.'
在电影《码头风云》中，特里·马洛伊哀叹自己浪费的潜力，说道：“我本可以是一个竞争者。”
你能说得更具体些吗？
In 'The Princess Bride', Vizzini repeatedly asks this phrase in frustration during the battle of wits.
在《公主新娘》中，维齐尼在智斗中反复用这句话表达挫败感。
Prepare the learner guide for this word
可生成：学习解释 Learner guide。只有点击后才会开始生成。
Dictionary facts from BRIDGEDICT_CURATED_MODAL, CEFR_J.