A: Since oil prices are very likely to continue to rise on a daily basis, I suggest you top up your tank when you're at the pump rather than partially fill your tank as a way to save some money.

B: I think my strategy of filling half full will give me more value for money.

A: OK. Let's compare. Let's say our tanks are now empty and I fill my tank full and you fill yours half full. Assuming that our usage is the same, that means you'll have to gas up when my tank is half full. And you'll be filling at a higher price now while I'm still running on the gas which we filled up ealier that's cheaper. Now, which strategy gives more bang for you buck?

Are there any mistakes? A's comparison doesn't flow smoothly to me but don't see what's wrong.

Thanks in advance.
I don't have any major problems with this dialog. One change I guess I might make is to say "And you'll be filling at a higher price now while I'm still running on the gas which we bought filled up ealier that's cheaper."
There are a number of what might be considered awkward formulations in the dialog but none that really grate on the ear. I wouldn't be at all surprised to hear or participate in a very similar dialog.
earlier ( I believe it is a typo.)
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RayH, I have a feeling that the akward formulations that you pointed out are scattered all over the piece which is why you didn't attempt any rephrasing or you would almost rewrite the entire piece. However, I would really appreciate if you could at least point out a major one and attempt a improvement so non-native speaker like me will know what's considered awkward and hopefully will not repeat the same mistake. Thanks in advance.

Thanks, Yoong Liat. Yes, it is. But I appreciate your help.
As I said in my original answer there are no really glaring errors in your dialog. Any changes I make would feel more like nitpicking than actual help. The awkward formulations I mentioned are nothing more severe than might be expected from a rushed native speaker. If I were to read your dialog without knowing who wrote it I would have very few clues that it wasn't written by a native speaker.

Relax, your English is very good. But then I suppose your command of the language got to where it is because you haven't relaxed. Emotion: smile
Thanks, RayH. I thought you were relunctant to change the original writing because you think it woudl be unfair to rewrite someone's work when the 'mistakes' are small. I just wanted to learn as much as possible. I think I was being too greedy. Thanks again.
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Nothing will bring down prices today except a tipping point in perception. Getting off and doing something to increase out petroleum supplies would be an improvement. Letting Cuba drill the Gulf is about par for the course. Any speculation in petroleum markets is justified by our record of ignorance in defining a cogent energy policy. And now our U.S presidential candidates Obama and McCain are talking about it, the issues surrounding recent discussions on US offshore drilling for oil has significant impact for all Americans. [url=http://pollclash.com ]US Offshore Oil Drilling- McCain vs. Obama[/url]