苦练: practise hard; drill diligently 短语和例子苦练过硬本领 master first-rate skills; spare no efforts in mastering first-rate skills; make oneself fully competent for one's task; 苦练杀敌本领 practise hard to
苦练杀敌本领: practise hard to master the military skill
过硬: have a perfect mastery of sth.; be really up to the mark; be able to pass the stiffest test 短语和例子过硬本领 be perfect at a skill; 过硬操作技术 a perfect mastery of operational technique