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to start to say; to attempt to say; to be about to say; to break off (mid-sentence)
to speak to; to address
何か言い掛けて黙った。
I started to say something and fell silent.
彼女は言い掛けているが止まった。
She was about to say something but stopped.
言い掛けた言葉を飲み込んでしまった。
I swallowed the words I had started to say.