To attend something for one time, as a visitor.(verb)
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Use "sit in" in a sentence
"Ironically the Tim-3 gene turns out to sit in a location where no scientist would ever have dreamed to look: smack on the chromosome that determines certain types of allergic reactions."
"But it is flattering that Boris dives deep into the sea to bring me conch shells and necks of two-thousand-year-old amphoras, which should sit in museums instead of the pockets of my backpack."
"Grisha invites us to sit in armchairs as he produces a small key out of the top drawer of his desk."