This is a regular verb. It follows the conjugation pattern of the verb hablar.
PresentPresente
Ella expresa sus ideas con mucha claridad.
She expresses her ideas very clearly.
PreteritePretérito indefinido
Expresó su opinión en la reunión.
He expressed his opinion in the meeting.
ImperfectPretérito imperfecto
De niño, expresaba sus sentimientos dibujando.
As a child, he expressed his feelings by drawing.