Some important idioms:

1. A penny for your thoughts: this idiom is used as a way of asking someone what they are thinking about.

2. Add insult to injury: When people add insult to injury, they make a bad situation even worse.

3. A hot potato: This idiom is used to speak of an issue (especially in current affairs) which many people are talking about.

4. Once in a blue moon: This is used when something happens very rarely.

5. Caught between two stools: When someone finds it difficult to choose between two alternatives.

6. See eye to eye: This idiom is used to say that two (or more people) agree on something.

7. Hear it on the grapevine: This means ‘to hear a rumour' about something or someone.

8. Miss the boat: This idiom is used to say that someone missed his or her chance at something.

9. Kill two birds with one stone: This means ‘to do two things at the same time'.

10. On the ball: When someone understands the situation well.

11. Cut corners: When something is done badly to save money. For example, when someone buys products that are cheap but not of good quality.

12. To hear something straight from the horse's mouth: To hear something from the authoritative source.

13. Costs an arm and a leg: When something is very expensive.

14. The last straw: The final problem in a series of problems.

15. Take what someone says with a pinch of salt: This means not to take what someone says too seriously. There is a big possibility that what he/she says is only partly true.

16. Sit on the fence: This is used when someone does not want to choose or make a decision.

17. The best of both worlds: All the advantages.

18. Put wool over other people's eyes: This means to deceive someone into thinking well of them.

19. Feeling a bit under the weather: Feeling slightly ill.

20. Speak of the devil!: This expression is used when the person you have just been talking about arrives.

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"Nay! man is evidence against himself. Though he puts forth his excuses." Holy Qur'an (75:14-15)