Flying without wings is impossible.
You're so impassable.
The mountain road was impassable because of the huge quantities of snow on it.
Those guards outside the palace are simply impassive.
The root word or base word of "impassable" is "pass."
Pass
The word "impassable" is an adjective. It describes something that cannot be passed or crossed.
The spelling is impassable (blocked, unnavigable).The similar word is impossible (not possible).
The boy crashed his motorcycle in the ravine.
Impassible has a root word, "pass." "Im-" is a prefix, and "-able" is a suffix.
Can you use the word concluding in a sentence? Done.
You can use the word Truss in a sentence like this.
Just use it! Or do you mean, can you use the word beheld in a sentence.