The rules about capital letters and currency are the following: you don’t use a capital letter to spell out the whole name, therefore: pounds, euros and dollars. You do write capitals when you use the internationally recognised abbreviations, therefore GBP for pounds, EUR for euros, USD for dollars and CNY for Chinese yuan etc.
When writing in English you put the currency symbol in front of the digits, so £10, €150 or $20.
Have you ever overheard some rather strange terms for money? Let us know in the comments below.

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