他们正在调查事故原因。

Tāmen zhèngzài diàochá shìgù yuányīn.

They are currently investigating the cause of the accident.

民意调查显示，百分之七十的人都满意房屋政策。

Mínyì diàochá xiǎnshì, bǎifēnzhī qīshí de rén dōu mǎnyì fángwū zhèngcè.

Public opinion polls show that 70% of the people are satisfied with the housing policy.

老师让我们调查同学们最喜欢的运动。

Lǎoshī ràng wǒmen diàochá tóngxuémen zuì xǐhuān de yùndòng.

The teacher asked us to survey which sports our classmates like the most.