-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
希望對你有所幫助。