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frequently; repeatedly; often; incessantly; constantly
eagerly; keenly; strongly; intently
hard; terribly; extremely; severely
彼女はしきりに時計を見ていた。
She was repeatedly looking at her watch.
しきりに雨が降り続いている。
It keeps raining incessantly.
しきりに質問をされて大変だった。
It was hard being asked questions repeatedly.