* bị động QKĐ: S + was/were (not) + V3/ed +(by+O) + time
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${66.}$ By whom was this house built?
Who was this house built by?
${67.}$ The huge stadium was being filled by the crowd.
→ bị động QKTD: S + was/were (not) + being + V3/ed +(by+O) + time
${68.}$ The thief was taken to the police-station by the police.
${69.}$ Badminton used to be played by Tom in the morning.
→ bị động "used to": S + used to + be + v3/ed +(by+O) + time
${70.}$ The key was found by Lan.