In Japanese, passive sentences are used very often, such as “Watashi wa sensei ni homerareta(my teacher praised me)”, “Purezento o agetara, yorokobareta(I gave him a present and he was happy),” and “Ame ni furarete, taihen datta(I had a hard time getting caught in the rain).” In Japanese language education, Japanese passive sentences are taught at an early stage. However, It is very difficult to use passive sentences properly and Japanese learners often use it in passive sentences that seem unnatural.

  Example 1 below uses a passive sentence to describe a bad event that day, but it feels a little unnatural to native Japanese speakers.

  Ex1) Kyoo wa sanzanna ichinichi datta yo. Densya de watashi no ashi wa fumareru shi, koohai ni watashi no deeta wa kesareru shi.

(Today was a terrible day. Someone stepped on my foot on the train,

My juniors have access to my data and deleted it.)

  If you change it like in example 2, it will become a natural sentence. In example 2, “I” is the subject of the passive sentence. When you say it this way, it feels natural as a sentence describing a terrible thing that happened to me. So where does this difference come from?

  Ex2) Kyoo wa sanzanna ichinichi datta yo. (Wawashi wa) Densya de  ashi o fumareru shi, koohai ni deeta o kesareru shi.

  “Watashi no ashi wa fumareta” and “Watashi wa ashi o fumareta” both use the passive form of the verb "fumareta," but they are different types of passive sentences. Passive sentences can be divided into two types: “direct passive” and “indirect passive.” “Watashi no ashi wa fumareta” is a “direct passive”, “Watashi wa ashi o fumareta” is an “indirect passive”. So, I will explain why in this case, using indirect passive sentences makes Japanese sound more natural.

   A direct passive sentence is a type of passive sentence in which the object of the active sentence becomes the subject of the passive sentence. In contrast, there is no such correspondence in indirect passive sentences.

<Direct Passive>
Active sentence:　Ani ga otooto o shikatta.
　　　　　　　　（The older brother scolded the younger brother.）

Passive sentence: Otooto ga ani ni shikarareta.

（The younger brother was scolded by the older brother.)

<Indirect Passive>

Active sentence: Doroboo ga watashi no saifu o nusunda.

                (A thief stole my wallet.)

Passive sentence: Watashi wa doroboo ni saifu o nusumareta.

Active sentence: Tonari no hito ga ichinichijyuu sawaide, benkyoo deki nakatta.

                (My neighbors were making noise all day so I couldn't study.)

Passive sentence: Tonari no hito ni ichinichijyuu sawagarete, benkyoo deki nakatta.

So, in Example 1, why is using a direct passive sentence unnatural and using an indirect passive sentence natural? This is because it is more Japanese-like to use “I” as the subject than to use “my feet” or “my data” as the subject. In Japanese, we usually use “I” as the subject when we talk about my terrible day that happened to me. Because the subject of what happened to me is “me” and not “my feet.”

However, there are some languages such as English and Chinese that do not have indirect passive sentences, so some Japanese learners wonder why the sentence “Watashi no ashi wa fumareta” is unnatural and find it difficult to understand why it is necessary to say “Watashi wa ashi o fumareta.”