Question

main verd of this sentence - he had won the competition​

Answer 1

Had won, because it is related to the subject of the sentence 'He', this means had won is the main verb

Answer 2

Answer:

The main word of this sentence (in my opinion) is He

Explanation:

Because if we remove the word 'The competition' then the sentence 'He had won' had meaning.

But if we remove 'He' Then the sentence 'Had won the competition' didn't have a meaning