有些单词的用法忘了..希望有人能帮帮忙

will:用于将来时,后边跟动词的原形.一般用于说话时做出的决定.比如：（门铃响了）I will open the door.我去开门
would:可以是will的过去时,也可以表示委婉的请求.如：1He said he would go to the party.他说他会去参加聚会（过去）2Would you like to have a cup of coffee?您想要那杯咖啡马?
could:可以理解成是can的过去时,也可以表示委婉的请求.如：1、I could read a book when I was 4.我四岁的时候就会读书了2Could I use your pen,please?我能用用你的笔么?
should:应该,也可以理解成shall的过去时.如：You should do your homework every day.你应该每天做作业.2、I thought I should leave.我想我要离开了（过去）
would't:=would not,would的否定形式,参照would用法
could't=could not见could
should'd=should not,见should
won't=will not,见will
need't=need not,不需要,一般用法为,need (not) to do Sth.与don't need有区别.don't need Sth
can't=can not 不能,can的否定形式,相信你知道can的用法,我不多说了

我也有些混淆了```期待答案~！楼下的答案不错~！