the sons of Gershon shall carry, under the orders of Aaron and his sons. And so shall each one know to which burden he ought to surrender
Other versions
King James Version
At the appointment of Aaron and his sons shall be all the service of the sons of the Gershonites, in all their burdens, and in all their service: and ye shall appoint unto them in charge all their burdens. English Standard Version
All the service of the sons of the Gershonites shall be at the command of Aaron and his sons, in all that they are to carry and in all that they have to do. And you shall assign to their charge all that they are to carry.New International Version
All their service, whether carrying or doing other work, is to be done under the direction of Aaron and his sons. You shall assign to them as their responsibility all they are to carry.