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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)
説明の合間にユーモアを差し挟んだ。
I inserted humor between explanations.
議論に疑問を差し挟む余地はなかった。
There was no room to interject doubts into the discussion.
報告に私見を差し挟むのは控えてください。
Please refrain from inserting personal opinions into the report.