A committee has been set up to investigate the problem. ✬

It's my business to investigate such things. ✬

The government appointed a committee to investigate the accident. ✬

Let's go and investigate. ✬

Let's investigate. ✬

Investigate the cause of it. ✬

I came here to investigate Tom's death. ✬

We'll investigate the matter. ✬

The police promised to investigate the matter. ✬

Tom heard a noise and went to investigate. ✬