The price range is from $50 to $300.

价格范围是从50美元到300美元。

Are these wholesale prices?

这些是批发价吗?

Yes, and we offer generous discounts for large orders.

是的，对于大量订货可以折扣大些。

Do you accept payment by quarterly statement?

接受按季度结算付款吗?

We only accept payment by irrevocable L/C.

我们只接受不可撤销的信用证付款方式。

range from … to… (在……到……内)变动;显示不定(或不等)

irrevocable a.不可改变的