A rainy day ( দুর্দিন ) Everybody should save something for rainy day.
In order to ( উদ্দেশ্য ) He came here in order to meet my mother.
be on ones back ( একেবারে কুপোকাত )
Slow coach ( অলস প্রকৃতির লোক ) You cannot expect much from a slow coach like him.
At bay ( কোনঠাসা ) The tiger was at bay in the bush.
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.