Question

What is the complete subject and complete predicate? I am confused.

Examples:
Back into the river went the little balls of platinum.

The platinum might then become gold, according to one theory.

Does the complete predicate include everything else with the verb phrase?

Answer 1

The complete subject is the noun which "owns" or "performs" the verb plus any articles and adjectives (including adjective phrases) associated with that noun.
The complete predicate is everything else.

Explanation:

In the examples below `color(red)("complete subjects")` are in `color(red)("red")`
and `color(blue)("complete predicates")` are in `color(blue)("blue")`.

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`color(blue)("Back into the river went") color(red)(" the little balls of platinum")`.

This might be easier to see if we rearrange the sentence so the subject comes first:
`color(red)("The little balls of platinum"color(blue)(" went back into the river went") )`.

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`color(red)("The platinum")color(blue)(" might then ""become gold, "" according to one theory")`.

This one is relatively straight forward although the predicate is a bit detailed.

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`color(blue)("Does")color(red)(" the complete predicate")color(blue)(" include everything else with the verb phrase")`?

Questions can be tricky. I would suggest converting into a declarative form:
`color(red)("The complete package")color(blue)(" does include everything else with the verb phrase")`.

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