first investigation的用法和样例：
例句
- Use methods that permit direct investigation of the question.
使用直接调查研究问题的研究方法。 - Apart from investigating complaints, The Ombudsman can initiate direct investigations of her own volition and may publish investigation reports of public interest.
除了调查投诉外，申诉专员还可以主动展开直接调查，并公布涉及公众利益的调查报告。
