3 sentences

1. 曾经，日本人在非正式和正式场合都穿和服。

   céng​jīng, rì​běn​rén zài fēi​zhèng​shì hé zhèng​shì chǎng​hé dōu chuān hé​fú.

   At one time, Japanese people wore kimonos for casual and formal occasions.

   Source: UM-Corpus: Education

2. 和日语中的所有东西一样，有正式和非正式的方式可以说出一切。

   hé rì​yǔ zhōng de suǒ​yǒu dōng​xi yī​yàng, yǒu zhèng​shì hé fēi​zhèng​shì de fāng​shì kě​yǐ shuō chū yī​qiè.

   As with everything in Japanese, there are formal and informal ways to say everything.

   Source: CCMatrix

3. 了解如何以及何时道别，通常是很困难的，即便是在非正式的场合也是一样。

   liǎo​jiě rú​hé yǐ​jí hé​shí dào bié, tōng​cháng shì hěn kùn​nan de, jí​biàn shì zài fēi​zhèng​shì de chǎng​hé yě​shì yī​yàng.

   Knowing how and when to say goodbye is often difficult, even in informal situations.

   Source: CCMatrix