In the first act Iago makes ironical statements to connote Cassio negatively, that reveal disdain and envy.

He provides only necessary information, he shows his aim, but he makes understand there’s more to know, through the suspense.

He plots his plain with the power of words; he addresses to Roderigo with the use of imperative, to line up him against the Moor.

He’s phoney and he hides his emotion using language, and making double cross he gains Othello’s faith.