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to insert
to interrupt; to slip in a word
to harbor (e.g. doubts); to harbour; to entertain (e.g. a theory)
会議中に意見を差し挾むのは難しい。
It's hard to interject an opinion during a meeting.
先輩の話に口を差し挾んでしまった。
I accidentally interrupted my senior's conversation.
余計な一言を差し挾んだ。
She inserted an unnecessary remark.