NET
48 So you testify that you approve of the deeds of your ancestors, because they killed the prophets and you build their tombs!
Darby
48 Ye bear witness then, and consent to the works of your fathers; for *they* killed them, and *ye* build [their sepulchres].
KJV
48 “Truly ye bear witness that ye allow the deeds of your fathers: for they indeed killed them, and ye build their sepulchres.”