Third-person singular simple present indicative form of crack.(verb)
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Use "cracks" in a sentence
"The shot was answered with a series of cracks from the other side of the room, where a group of policemen had joined in the gunfight."
"Even the best college support systems are often inadequate to the challenge, and the number of students who slip through the cracks is very high."
"Bacteria have also been shown to be able to survive virtually hard vacuum, which raises the interesting possibility that the earliest living cells originated in cracks in rocks in space, and arrived on Earth via infalling bolides."