How to use "expressly" in a sentence

It was further matured, and the faith of all the then thirteen States expressly plighted and engaged that it should be perpetual, by the Articles of Confederation in 1778

I therefore consider that, in view of the Constitution and the laws, the Union is unbroken; and to the extent of my ability I shall take care, as the Constitution itself expressly enjoins upon me, that the laws of the Union be faithfully executed in all the States

Shall fugitives from labor be surrendered by national or State authority? The Constitution does not expressly say

May Congress prohibit slavery in the Territories? The Constitution does not expressly say

MUST Congress protect slavery in the Territories? The Constitution does not expressly say.