List some idioms and phrases which can be use for formal letter

Dear Student,
Given below are some of the idioms, along with the meanings, which can be used in the letter. Please refer to the Website to find the format of a letter.

• between a rock and a hard place - to be in difficult situation
• a leopard can't change its spots - a person cannot change his character
• not my cup of tea - something that doesn't interest me
• at the drop of a hat - without hesitation or for a good reason
• blessing in disguise - a good that has evolved from something terrible
• to bury the hatchet - to end a quarrel and become friendly
• a stroke of luck -  food fortune

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