被字句
RulePatient + bei + (agent) + verb + extra: passive, "to be V-ed".
Curiosity
How do you make the one affected the subject, as in "I was praised by the teacher"?
Intuition
bei puts the affected one (patient) first and the agent after bei. If ba takes the doer's viewpoint, bei takes the receiver's: they mirror each other.
Visualization
From active [teacher][praised][me], move the patient me to the front: [me][bei][teacher][praised].
Active (agent as subject)
老师agent表扬了verb我patient
被 construction (patient as subject)
我patient被被 (passive)老师agent表扬了verb
Essence
The agent after bei can be omitted (wo bei piping le). Like ba sentences, the verb usually carries a result or le. Useful when the agent is unknown or left out.
Examples
我被老师表扬了。
I was praised by the teacher.
杯子被打破了。
The cup was broken.
蛋糕被弟弟吃了。
The cake was eaten by my little brother.
Mini-quiz
Which bei sentence means "my bike was stolen"?