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to go uninvited; to call on without an invitation; to barge in on; to gatecrash
to throng to; to crowd into; to converge upon; to pile in
ファンが自宅に押し掛けた。
Fans barged in at the home.
報道陣が押し掛けている現場は混乱していた。
The scene with the press swarming was chaotic.
突然押し掛けるのは失礼だ。
It's rude to show up uninvited.