blood brother

名词 blood brother:

1. a male with the same parents as someone else
   同义词：brother
2. a male sworn (usually by a ceremony involving the mingling of blood) to treat another as his brother

1. Knowledge is often the blood brother of practice.
   知识与实践往往是不可分的。
2. Bob's like a blood brother and would do anything for me.
   鲍勃象亲兄弟，愿意为我两肋插刀。