idioms

1. What is the difference between the idiot and the idiom?
2. http://www.merriam-webster.com/dictionary/idiom?show=0&t=1314060862
3. My house is at a stone's throw from my school.
4. My problem in maths.was a battle of wits.
5. His  dealings are always fair and square  http://www.merriam-webster.com/dictionary/fair?show=0&t=1314061195e.
6. Potatoes are very costly when in short supply.
7. He borrowed money from everyone so he was in deep waters.
8. If you want to help your mummy in her business you must learn the tricks of the trade.
9. Life is not  a bed of roses.
10. His earnings was a drop in the ocean.
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