Thoroughly practiced, rehearsed, or understood.(adjective)
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Use "down pat" in a sentence
"After recovering from her initial swoon on the love seat in her Hilton sitting room (or near-swoon: it hadn't put her out of action long), there was a flying at Farraday with fingernails unsheathed, as if she Were blaming him for having brought them to this murdering town in the first place; there was a raging at Lasko and Jury, the messengers who had brought the bad news; there was a stalking of the room, as if she'd got the stage blocking down pat Go to window."
"They had the terrors of postmodernity down pat but seemed to be missing the sublime."