表示原因的用语，例如：

The age of the product was a contributory factor in the accident.

预计结果用语，例如：

We can anticipate the following consequences:...

表示需要考虑，例如：

Let us focus our attention on...

举例用语，例如：

Here, I am just showing you a few examples of ...

展示胶片用语，例如：

Allow us, then, at this point to present some slides.

读报告的开场用语，例如：

My paper is a literature review.

提问用语，例如：

My I ask a question? This is an extremely difficult question to answer.