I saw a goose and a duck at the pond (singular)
We saw geese and ducks at the pond (plural)
Is the plural version correct?
Specifically, what about the pond? Is it also have to change in plural or not?
I saw a goose and a duck at the pond (singular)
We saw geese and ducks at the pond (plural)
Is the plural version correct?
Specifically, what about the pond? Is it also have to change in plural or not?
It depends on what you want to say.
If you saw one goose (not previously identified) and one duck (not previously identified) at the pond, you would say "I saw a goose and a duck."
If you saw more than one goose (not previously identified) and one duck (not previously identified) at the pond, you would say "I saw geese and a duck."
If you saw one goose (not previously identified) and more than one duck (not previously identified) at the pond, you would say "I saw a goose and ducks."
If you saw more than one goose (not previously identified) and more than one duck (not previously identified) at the pond, you would say "I saw geese and ducks."
Meaning determines grammar.
EDIT: It is misleading to say that a sentence is singular or plural.
Nouns and verbs are singular or plural depending on meaning. There is no requirement that all the nouns in a sentence have the same number.
Whether a noun is singular or plural depends only on how many of that thing there are. If you're only talking about one pond, then it's "the pond"; if there are two or more ponds, it's "the ponds".
To decide between "the pond" and "the ponds", you only need to consider how many ponds you're talking about. Nothing else matters, including the number of ducks, geese or anything else.