医院正在对事故进行调查。

The hospital is holding an ___enquiry into the accident.

政府已对腐败指控展开正式调查。

The government has launched a formal ___enquiry into the corruption allegations.

成立了一个独立调查组来审查系统故障的原因。

An independent ___enquiry was set up to examine the causes of the system failure.