This is the 15393rd most frequent German word.
vergisst
"Vergisst" means "forgets."
Here, 'vergisst' is used to describe repeatedly forgetting to do the homework.
Er vergisst immer, seine Hausaufgaben zu machen.
He always forgets to do his homework.
In this context, 'vergisst' describes the habitual forgetfulness of bringing keys.
Marie vergisst oft, ihre Schlüssel mitzunehmen.
Marie often forgets to take her keys with her.
Here, 'vergisst' expresses a general observation about how people might overlook the small details in life.