雷打不动

1. • not shaken by thunder (idiom) the arrangements are unalterable
2. • to adhere rigidly to regulations
3. • will go ahead whatever happens (of an arrangement or plan)

Character by character

• 雷(léi)surname Lei
• 打(dǎ)a semantically light, transitive verb that is combined with various grammatical objects to form compound verbs and verb-object phrases with a diverse range of meanings
• 不(bù)no
• 动(dòng)move