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to try to unsettle someone; to throw off balance
相手に揺さぶりを掛けて交渉した。
I negotiated by pressuring the other party.
彼は交渉の場で相手に揺さぶりを掛けた。
He tried to unsettle the other party during negotiations.
揺さぶりを掛ける戦術を使った。
I used a pressuring tactic.