Can you explain "logical subject-predicate relationship" and "predicate of copula verb"?

A sentence often contains more than one "subject-predicate relationship", for example, I saw two people crossing the road.

I saw two people crossing the road. [I think] is a pair of subject and predicate, and [two people walk by] is also a pair of "subject and predicate"

Logical subject-predicate is [logic], that is, it is not Allah's predicate, because a sentence can only have a pair of subjects and predicates;

The logical predicate in English is [participle or infinitive]

In the above example, I saw the subject and predicate of the sentence, and the intersection of two men is the logical subject and predicate.

Two logical subjects, crossing logical predicates

And [two men] is the object in the whole sentence, and [crossing the street] is the object complement in the whole sentence.

There are many forms of logical subject and predicate, which can generally be changed into object clause, attributive clause or adverbial clause;

For example, the above example can be changed to, I saw two people crossing the road. (object clause)

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Predicates are simple and are used to modify the subject after verbs.

Predicates can include [nouns, adjectives, adverbs, prepositional phrases, infinitives, -ing]

The copula verbs are [am, is, are, look, feel, smell, taste, sound, seem] and so on.

[main table] is generally used together.

For example, you look beautiful. You 15 years old. He is in the park.

In the above example, [pretty], [15 years old] and [in the park] are predicates of the copula verbs, which are used to modify the subject.