The term present perfect progressive often confuses students who are learning English grammar.

By next June, the future perfect progressive will be the tense we focus on in class.

Teachers explained that the past perfect progressive indicates a continuous action that had been happening before another past event.

The neurologist explained that the child's symptoms were consistent with progressive infantile poliodystrophy.

The neurologist explained that progressive sclerosing poliodystrophy typically presents in early childhood with refractory seizures and developmental regression.

At the historical society's reenactment, the musicians taught the audience the steps of a progressive longways formation, reviving an old New England line dance.

The neurologist explained that progressive multifocal leukoencephalopathy is a rare but serious complication in immunosuppressed patients.

Teachers often explain present perfect progressives by comparing them to simpler tenses.