I want to offer flowers to the many people who’s lives were taken away on 9/11.
offer flowers は花を手向けたいと言う意味として使います。花を手向けると言うぴったりの意味はありませんけど、なるべく近い意味のoffer (捧げる)を使いました。
花屋さんでは、I would like to buy flowers to offer to the many lives that were lost due to 9/11. (９／11で命を奪われた人々に手向けられる花を買いたいですと言う意味です。)と伝えれば良いと思います。
お役に立ちましたか？^_^
1) I want to give flowers to the victims of the 9.11 incident.
2) I want to offer flowers to the people whose lives were sacrificed on the 9.11 incident.
1) & 2) "9.11で犠牲になった人たちに花を手向けたい" という意味です.
9.11で：the 9.11 incident.
犠牲になった人たちに：to the victims / to the people whose lives were sacrificed.
花を手向けたい：I want to give flowers / I want to offer flowers.
アメリカ合衆国 
モロッコ 
