Modal Perfect

[leftsidestory]

I have a question regarding the modal verb and how it turns into infinitive when used in a past participle.

The principle is simple. But there are some examples that confuses me.

For example,

“Ik heb dit boek kunnen lezen.” This is very simple to understand, as “Ik” carries both the verbs “kunnen” and “lezen”

But,

“We hebben alles zien veranderen” is a bit confusing to me, as the action “zien” is carried out by “We”, while “veranderen” is carried out by “alles”. How would you know that this sentence wouldn’t be translated into, for example “We have seen changing everything”

[LeSNT2]

In general I teach my students: the first verb (finite verb) is conjugated, all other verbs are not conjugated. Of course this is for sentences in the present tense. In the past participle more than one verb can change (e.g. Ik heb dat niet gedaan, 'heb' and 'gedaan' are not infinitive). In the past participle only two verbs can be conjugated. The third, fourth, etc. verb is always infinitive. Examples:

Ik kan me niet voorstellen dat ik ooit zoiets gezegd zou hebben. = 'zou' + 'gezegd' are conjugated in the sub clause.
Zoiets zou ik ook wel gezegd kunnen hebben. = 'zou' + 'gezegd' are conjugated in the main clause.
Die brieven hadden niet verstuurd mogen worden. = 'hadden' + 'verstuurd' are conjugated in the main clause.

So for your sentence 'hebben' and 'veranderen' are conjugated. 'veranderen' is also the infinitive but that's just because the participle is formed like that. If you would change the sentence with another verb you see it:

Ik heb alles gekookt zien worden. = 'heb' + 'gekookt' are conjugated, the other verbs are infinitive ('zien' + 'worden').

Hope this is clear!

[leftsidestory]

I guess my question was not quite clear.
I have no problem really with the rule itself.

What confuses me is how to “analyze” the sentence grammatically so that I do not misunderstand the sentence.

My example: We hebben alles zien veranderen would translate into We have seen everything change

In the English translation, it is quite clear that it is the “We” that “see”, and it is the “everything” that “change”. But in the Dutch sentence, “zien” and “veranderen” both follow “alles”, which makes me confused if these actions “zien” and “veranderen” are carried out by “We” or by “alles”.
I am not sure if I am clear here.

Another example could be: Je hebt me dat nooit horen zeggen
The English translation would be : You have never heard me say that. But how do you tell it is the “Je” that “horen” and me that “zeggen”, not “Je” doing both “horen” and “zeggen”?

And another example is: De hele wereld heeft mij zien dansen.
It is a simple one, but how do I know if it is the “hele wereld” that is “zien” and “dansen” or it is “mij” that is “zien” and “dansen”?

[LeSNT2]

Ah, now I get your 'problem'. It is confusing, I agree. A lot of it we get out of context. For example:

"Je hebt me dat nooit horen zeggen." There is 'horen' (hear) and 'zeggen' (say) in one sentence, it's not likely that one person is saying ánd hearing at the same time. So 'me' is saying something (or not in this sentence, because of the 'nooit') and 'je' is hearing something.

So our word order rules are not about who is doing what, it's about the type of word. We can say 'Ik sla jou' (I hit you) or 'Jij bent geslagen door mij.' (you're were hit by me) and even 'Jij bent door mij geslagen.' (same meaning as previous sentence) So you need to understand the words and the context to know who is doing what, you can't know it bij analyzing the conjugation of the verbs or the place of the words.

Hope this answers your question