釘是釘，鉚是鉚（釘是釘，鉚是鉚）　

◎ 釘是釘，鉚是鉚 dīng shì dīng mǎo shì mǎo

[be accurate in what one works;be conscientious and meticulous] 形容辦事認(rèn)真,一絲不茍。也作“丁是丁,卯是卯”