调查的英文：
investigation
inquiry
investigate
survey
survey
opinion poll

参考例句：

Sit on; investigate
开会研究;调查

No investigation, no recognition.
没有调查，就没有发言权。

He's assisting us with the canvass.
他在协助我们调查。

See into; look into;see through
查看;调查;了解;看穿

A preliminary hearing
【法律】初审,调查庭

To study geology or make geologic investigations.
研究地质学或作地质调查

" according to the latest census, our population has decreased. "
根据最近调查,我国的人口减少了。

undercover FBI agents.
从事秘密调查的联邦调查局密探

Take their friends, start a canvass.
就先从他们的朋友开始入手调查。

An opinion poll marred By faulty methodology.
被错误地损害了效果的观点调查

investigation是什么意思：
n. 研究；调查

No investigation, no recognition.
没有调查，就没有发言权。

You have to investigate into this affair.
你必须调查研究这件事。

They investigate corruption.
他们调查贪污。

inquiry是什么意思：
n. 探究；调查；质询

Is this the baggage inquiry area?
查询行李情况是在这里吗？

They held an inquiry into the incident.
他们对这一事件展开调查。

To keep in custody and hold an inquiry
拘押查究

investigate是什么意思：
v. 审查；调查，研究

No investigation, no recognition.
没有调查，就没有发言权。

You have to investigate into this affair.
你必须调查研究这件事。

They investigate corruption.
他们调查贪污。