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to keep watch (e.g. on a suspect); to be on the lookout (for); to lie in wait (for); to keep under surveillance; to stake out
to spend a lot of money (on); to treat oneself (to); to splurge (on); to invest (in)
to paste; to stick; to affix
彼らは容疑者を張り込んでいる。
They are staking out the suspect.
取引があるまで３日間倉庫に張り込んだ。
He staked out the warehouse for three days until the deal happened.
ターゲットが現れるまで駅の入口に張り込む計画だ。
The plan is to stake out the station entrance until the target appears.