Third-person singular simple present indicative form of blackboard.(verb)
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Use "blackboards" in a sentence
"All the horses attached to the blackboards were the picked ones of the"
"Initially, many villagers were concerned that blackboards don't really belong in a mosque, and kept their girls and boys away."
"To often in science fiction, we're presented with a theorist's blackboards full of equations, which are then reduced to practice without much trouble at all."