At a stretch( একটানা ) He can run ten miles at a stretch.
A bolt from the blue( সম্পূর্ন অপ্রত্যাশিত ) The news of his father's death came to him as a bolt from the blue.
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.
host in himself( একাই একশ )
In order to ( উদ্দেশ্য ) He came here in order to meet my mother.
By far( সর্বাংশে ) He is by far the best boy in the class.