John and Mary run. Jon and Mary is complete subject or simple subject?It's a grammer question. Thx!

"John" and "Mary" are each simple subjects -- subjects
without any words describing them. In order for it to be a complete subject, there would
have to be modifiers. If the sentence said "Big, hairy John and sweet, pretty Mary run,"
that would be a complete subject. In fact, it would be two complete
subjects!

Here, though, you have no modifiers. Don't be
fooled by the fact that the subject includes more than one word. You can have a simple
sentence with two subjects, like this one.

Think about it
like this: this sentence is like two sentences squished into one. "John runs." "Mary
runs." In those sentences, there's no doubt that the subjects are simple. Those subjects
haven't changed in your sentence, so they are still simple
subjects.