Final answer:
In Iago's monologue, his regret in getting Cassio in trouble is indicated by several words, such as 'evil,' 'blank,' and 'wish.'
Step-by-step explanation:
In Iago's monologue, there are several words that indicate his regret in getting Cassio in trouble. One example is in the line 'I am he who knew what it was to be evil,' where Iago admits his wrongdoing and regrets his actions. Another word that shows his regret is 'blank' in the line 'My great thoughts as I supposed them, were they not in reality meagre?' This implies that Iago feels remorse for his misguided beliefs and actions. Lastly, the word 'wish' in the line 'Had guile, anger, lust, hot wishes I dared not speak,' suggests that Iago has regrets about the desires and intentions he had but didn't act upon.