[N(recipient)]は/が [N(actor)]に [N(object)]を [V(passive)]

When one person (the actor) acts directly on an object and this action affects the another person (the experiencer), the sentence can be recast from the recipient’s point of view using a passive verb.

田中さんは 山下さんの おにぎりを たべました。
Tanaka-san ate Yamashita-san’s onigiri.

山下さんは 田中さんに おにぎりを 食べられました。
Yamashita-san’s onigiri was eaten by Tanaka-san.

Notice that this time, the experiencer is not the direct object – Tanaka-san is not being eaten himself. However, because he is affected by the action, we use a passive verb. Because the direct object is not the experiencer this time, it stays as it is with を.

This is known as the indirect passive, because the direct object does not become the topic.

This form is often used to describe an action from the recipient’s viewpoint when something unfavourable happens.

When there is no need to say who the actor is, that part can be omitted.

電車で 財布を 取られました。
I had my wallet taken on the train