Can junction boxes be covered in a basement ceiling?

I am installing recessed can lights new construction kind (not the remodel kind) in my basement i have started the work and i am using metal conduit as the main feed and branching off from several jboxes to the fixtures jbox with fmc. I now find out that I can not cover jboxes with drywall. How do i wire these cans if i can not use jboxes to feed wires from the main feed (conduit).