The conversation between human and AI assistant.
[|Human|] Find incorrect verb tense in this sentence: He was swimming in a pool.
[|AI|] The verb tense in that sentence "He was swimming in a pool" is not incorrect. It is in the past continuous tense, indicating an ongoing action that was happening in the past.
[|Human|] 
Find incorrect verb tense in this sentence: He was swimming in a pool.