想不到他突然出现在我的生日派对，太惊喜了！

Xiǎngbudào tā tūrán chūxiàn zài wǒ de shēngrì pàiduì, tài jīngxǐ le!

I never thought he would suddenly show up at my birthday party, what a pleasant surprise!

最近我家里的网络经常出现问题。

Zuìjìn wǒ jiā lǐ de wǎngluò jīngcháng chūxiàn wèntí.

Recently, my internet at home keeps having problems.

他的电脑又出现问题了。

Tā de diànnǎo yòu chūxiàn wèntí le.

His computer has a problem again.