5. Would you tell me the difference so that I can make a choice?
你能告诉我有什么不同，以便我做出选择吗？
还能这样说：
In order to choose the right thing, please tell the distinctions among them.
I would like to know the difference so that I can make a choice.
应用解析：
a great choice of 大量供选择的物品等；
at one's own choice 随意挑选，自由选择；
choice of the end covers choice of the means. 只问目的，不问手段

6. Do you mean the life insurance is against accidents?
你的意思是人寿险是预防事故发生的吗？
还能这样说：
Is the life insurance against accident?
Can I avoid accidents if I accept the life insurance?
谚语：
Life is not all beer and skittles.
人生非只吃喝玩乐。

7. Generally speaking, aviation insurance is much cheaper than marine insurance.
空运保险一般要比海运保险便宜。
还能这样说：
On the average, marine insurance is more expensive than aviation insurance.
As a general rule, aviation insurance is cheaper compared with marine insurance.
应用解析：
cheap money 贬了值的钱，利息低的借款；
cheap entertainment 低级的娱乐；
cheap emotion 虚伪的感情；
cheap flattery 假意奉承

8. Let me explain why you need fire insurance.
我来解释一下贵方为什么要保火险。
还能这样说：
It can be explained why you need fire insurance.
Let me amplify the reason that you need fire insurance.
谚语：
Fire is a good servant but a bad master.
火是一把双刃剑。