The bricks
lbenah  (leb-ay-naw')
a brick (from the whiteness of the clay) -- (altar of) brick, tile.
are fallen down
naphal  (naw-fal')
to fall, in a great variety of applications (intransitive or causative, literal or figurative)
but we will build
banah  (baw-naw')
to build (literally and figuratively) -- (begin to) build(-er), obtain children, make, repair, set (up), surely.
with hewn stones
gaziyth  (gaw-zeeth')
something cut, i.e. dressed stone -- hewed, hewn stone, wrought.
the sycomores
shaqam  (shaw-kawm')
a sycamore (usually the tree) -- sycamore (fruit, tree).
are cut down
gada`  (gaw-dah')
to fell a tree; generally, to destroy anything -- cut (asunder, in sunder, down, off), hew down.
but we will change
chalaph  (khaw-laf')
to slide by, i.e. (by implication) to hasten away, pass on, spring up, pierce or change
them into cedars
'erez  (eh-rez')
a cedar tree (from the tenacity of its roots) -- cedar (tree).