And b, they have what's called a low expense ratio since they're easy to implement, you don't pay anyone to be brilliant to implement if for you.

但是他们的费用比率很低,因为这种做法很容易，你不需要,有多聪明就能去实施。

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Fuel taxes are easy to pay, efficient to collect, simple to understand, environmentally friendly, and directly related to use of the system.

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And it wasn't easy to pay off these loans, but it sure wasn't as hard as it is for a lot of kids today.

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"In the cities and around train and bus stations it is still easy to find pay phones, " said Adrian Krucker of Zurich, Switzerland.

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