en_tn_condensed/isa/33/11.md

You conceive chaff, and you give birth to stubble

This speaks of the Assyrians making plans as if they were conceiving and giving birth to their plans as a mother gives birth to a baby. This speaks of their plans being useless by comparing them to chaff. Alternate translation: "You make plans that are as useless as chaff and straw" (See: rc://en/ta/man/jit/figs-metaphor)

stubble

The dry pieces of plants that are left in the ground after the stalks have been cut.

your breath is a fire that will consume you

Here the Assyrians' plans are referred to as their "breath." This speaks of their plans causing them to die as if their plans would literally burn up their bodies. Alternate translation: "your plans will cause you to die" (See: rc://en/ta/man/jit/figs-metonymy and rc://en/ta/man/jit/figs-metaphor)