wǒmen xūyào diàochá yuányīn.

we

Breakdown of wǒmen xūyào diàochá yuányīn.

• 需要xūyào: to need
• 原因yuányīn: reason
• 调查diàochá: to investigate; survey

Questions & Answers about wǒmen xūyào diàochá yuányīn.

What is the basic grammar pattern of 我们需要调查原因。?

The sentence follows a very common Mandarin pattern:

subject + 需要 + verb + object

So here it is:

• 我们 = subject
• 需要 = need / need to
• 调查 = investigate
• 原因 = reason / cause

Mandarin often builds sentences in a very straightforward order, so this is structurally similar to We need to investigate the cause/reason.

Why is there no word for to before 调查?

Because Mandarin does not use an infinitive marker like English to.

In English, you say need to investigate.
In Mandarin, 需要 can be followed directly by a verb:

• 需要调查 = need to investigate
• 需要学习 = need to study
• 需要准备 = need to prepare

So to is simply not something Mandarin needs here.

Can 需要 really be followed directly by a verb?