The rule is: want takes a "to"-infinitive clause; can takes a bare infinitive (clause).
These are properties of those particular words, as arbitrary as their pronunciation and meaning: they simply have to be learnt along with those other arbitrary properties.
It might help to note that can is a modal, (like could, will, would, should, may, might, ...
The word must has two meanings as a modal verb: one indicates necessity, and the other probability.
The necessity meaning cannot be used about things in the past: instead, you use the past tense of have to. As an example, if you use reported speech you have to backshift the tense:
He said "I must go to the dentist"
He told me that he must go to ...
I suppose I know the difference.
Both sentences 2 and 3 indicate some unreal and hypothetical situations. The difference is that sentence 2 ( I would have liked to come with you) implies an unreal PRESENT situation, but sentence 3
(I would like to have come with you) is used to refer to a PAST unreal situation.
In other words, "I would have liked to ...
2 - You would say this if you know for certain they’re planning to talk to someone about this, or were making a strong assumption.
3 - You would say this if you were assuming they were thinking of talking to someone.
1 - This is the most general phrasing, and doesn’t really assume anything about them talking to someone, even though it references speaking to ...
1: If Jones was at work until six, he can't have done the murder.
it is not possible (now) that he did it (then)
2: If Jones was at work until six, he couldn't have done the murder.
it was not possible (then) for him to do / have done it (then)
Where in practice both assertions can only actually mean the same thing. If he couldn't have done the murder at ...
It is too simplistic to say "might have"+past participle is the past of "might".
It's true that "Might have"+past participle is used when we are discussing past events (completed events): e.g. I thought I might have forgotten my key, but then I found it in my pocket or He might have kissed her if he had been brave enough or She ...
Would is a modal, and like all modals has a variety of meanings, generally different from the same phrase without the modal.
In this case, to me it expresses a connotation: surprise, disapproval, or disappointment: something like "I didn't expect you to call the police" or "it wasn't necessary to call the police", or even "I wish you ...
may and might take the bare infinitive of the verb that follows
I may [to] go ---> I may go
I might [to] go ---> I might go
I may [to] have Covid 19 ---> I may have Covid 19
I might [to] have Covid 19 ---> I might have Covid 19
I may [to] have gone ---> I may have gone
I might [to] have gone ---> I might have gone
No English verbs have a ...
The structure 'might had' is ungrammatical. If you are using a modal auxiliary verb (might, may, could, etc) to express something in the past, it has to be in the format have + past participle.
I might have passed the exam if I had studied a harder.
You might have said something that made him angry.
He may have been at the party, but I can't be sure.
Without context, the examples you provided with “would” may be interpreted in the future or the past tense.
In most cases, these phrases come along with context, so here we know you are talking about the past tense usage of “would”.
Generally, “would” and “did” can be used as past tense verbs interchangeably without any difference.
In my experience, people ...
For me, using USA English, "Why would you do this?" is asking for my thought process. It is hypothetical; that is, it does not necessarily mean that I took the action. By contrast, "Why did you do this?" states that I did take the action, and is asking why I took that action.
If I did take the action, and you ask me, "Why would you ...
You haven't quoted the full sentence! It is:
It was a matter of chance that I should have rented a
house in one of the strangest communities in North America.
The should-less version would more naturally be "that I had rented" rather than "that I rented". I agree there would no real difference in meaning.
I also agree that "have&...
Have to X means to be required or forced to X.
So, I agree with you means you agree of your own free will. I have to agree with you means something is forcing you to agree.
The difference between this and plain "I agree" is that when you say "I have to agree", you are admitting you are wrong in light of some new information or evidence, ...
Both "can" and "could" are ok, but "can" is more natural assuming the sentence is trying to convey a universal truth.
Using "could" would make the sentence feel more hypothetical, or possibly make reference to a past time, while "can" seems to match the present tense of the first clause "you are".