If you use the present, past, or future perfect tense, make sure that you use the past participle and not the simple past tense.

              WRONG: I have swam in that pool every day this week.

              RIGHT: I have swum in that pool every day this week.

Irregular verbs like “swim” have different forms for the simple past tense and for the past participle used with the perfect tenses.

** If you “hear” a verb that contains have or had, check for a verb tense error.