The predicate of a sentence tells something about the subject. It tells what the subject does, did, is doing, or will be doing.
Examples:
What did the two friends do with the banana plant?
What did the monkey do?
What happened to the banana plant?
The answers to the questions above are the predicates of the sentences.
Cut the banana plant into two, got the top part of the plant, and started to grow tell us something about the subject.
The subject and predicate in sentences may be simple or complete.
The two friends cut the banana plant into two.
Simple subject: friends
Complete subject: The two friends
Simple predicate: cut
Complete predicate: cut the banana plant into two
The monkey got the top part of the plant.
Simple subject: monkey
Complete subject: The monkey
Simple predicate: got
Complete predicate: got the top part of the plant