The police carried out a thorough investigation.

警方展开了全面的调查。

《牛津词典》

He had made a thorough investigation. No wonder he knew so much about it.

他对此事做了彻底的调查, 怪不得他了解得那么多。

youdao

After a thorough investigation, many experts now believe that the streak was a run-of-the-mill jet aircraft contrail.

经过彻底的调查，许多专家现在认为，这条轨迹是一条普通的喷气式飞机尾迹。

youdao

The White House has promised a thorough investigation of the matter, and steps to guard against a repeat of the tragedy.

VOA: standard.2009.11.10

The Chancellor is also calling for a quick and thorough investigation of last week's NATO air strike on two fuel tankers, which had been hijacked by insurgents in Afghanistan's Kunduz province.

VOA: standard.2009.09.07

At a news briefing, State Department Spokesman Ian Kelly said the United States has been urging Sri Lankan authorities to open up the northern region to international organizations, and to conduct a thorough investigation of the charges.

VOA: standard.2009.10.22

In a statement, it said a "thorough investigation", involving the police, had proved inconclusive.

BBC: Bedford Hospital 'mystery wound' patient seeks answers

"We want a thorough investigation of everything that transpired, " Mr Aquino told a news conference.

BBC: Philippines president pledges Manila bus siege inquiry

The FBI conducted a thorough investigation and found "no ties to terrorism, " Mueller said.

CNN: Suspect: Boston bombing was payback for hits on Muslims