告诉听众内容要点

- there are five main aspects to this topic (...the first, ... the second, ...a third, ...another, ... the final)

- I am going to examine these topics in the following order (...first, ...next, ...after that, ...finally)

- I've divided my talk into five parts...

- I will deal with these topics in chronological order...

- I'm going to start with a general overview and then focus on this particular problem (...in general, ...more particularly).

- I want to start with this particular topic, and then draw some more general conclusions from it (...specifically, ... in a wider context).

- there are (a number of) factors that may affect...

- We have to take into account in any discussion of this subject, the following considerations.

- We all ought to be aware of the following points.

　　结束语

-In conclusion, I'd like to...

-I'd like to finish by...

-Finally...

-By way of conclusion...

-I hope I have made myself understood

-I hope you have found this useful

-I hope this has given you some idea/clear idea/an outline of...

-Let me end by saying...

-That, then was all I had to say on...

-That concludes our presentation...

-I hope I've managed to give you a clearer picture of...

-If there are any questions, I'd be delighted to...

-Thank you for your attention...

-Let's break for a coffee at this point

-I am afraid that the clock is against us, so we had better stop here

-You have been a very attentive audience---thank you