Stone's throw ( অতি নিকটে ) Our school is at a stone's throw form our house.
By and by( শীঘ্র ) He will come here by and by.
At large( স্বাধীন ) The anti-socials are still at large.
A rainy day( দুর্দিন ) Everybody should save something for rainy day.
A blessing in disguise( বিপরীতে হিত ; প্রথমে খারাপ হিসেবে মনে হলেও পরবর্তীতে ভালো হয় ) Sam's motorcycle accident was a blessing in disguise because he got enough insurance money.