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to collect; to put (it all) together; to integrate; to consolidate; to unify
to summarize; to aggregate
to bring to a conclusion; to finalize; to settle; to put in order
to establish; to decide
この資料をまとめておいてね。
Please put these materials together.
皆の意見をまとめるのは難しい。
It's hard to summarize everyone's opinions.
長い髪をまとめたほうがいいよ。
You should tie up your long hair.