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to assemble everything together
to do something as a group
全員がこぞって反対した。
Everyone came together in opposition.
若者たちがこぞっている人気の店に入った。
I went into a shop where all the young people were flocking.
毎年このコンサートには若者が挙るほど盛況だ。
This concert is so popular every year that young people flock to it.