Use "penetrable" in a sentence

1. Still clutching the material to his chest, he waits for the darkness to grow more penetrable before continuing his discovery of what the soldiers have done

2. "In reality," replied the latter, who, with his aristocratic glance and his knowledge of the world, had penetrated at once all that was penetrable in Monte Cristo, "Albert has not deceived us, for the count is a most singular being

3. The moon made the night extraordinarily penetrable and showed me on the lawn a person, diminished by distance, who stood there motionless and as if fascinated, looking up to where I had appeared—looking, that is, not so much straight at me as at something that was apparently above me