In the poem" Dulce et decorum est" What does the speaker see happen in the poem?

He sees and details in very graphic ways the terrible ways that men are dying around him. "An ecstasy of fumbling, fitting the clumsy helments just in time....floundering like a man in fire or lime....

"He plunges at me, guttering, choking, drowning..."

"White eyes writhing in his face. His handing face, like a devil's sick of sin..." "Blood come garling from the froth corrupted lungs..."