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to hold out; to extend (e.g. one's hands); to stretch; to reach out for
to thrust (javelin)
to offer (e.g. aid, help, etc.)
困っている人に手を差し伸べた。
I reached out to someone in trouble.
被災者に支援の手を差し伸べている。
I am extending a helping hand to disaster victims.
誰かに手を差し伸べることの大切さを学んだ。
I learned what it means to reach out to someone.