打退堂鼓
dǎ tuì táng gǔ
lit. to beat the return drum (idiom)
fig. to give up; to turn tail
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 (e.g. 打傘|打伞[da3 san3] "to hold an umbrella", 打電話|打电话[da3 dian4 hua4] "to make a phone call", 打針|打针[da3 zhen1] "to get an injection", 打手套[da3 shou3 tao4] "to knit gloves", 打氣|打气[da3 qi4] "to inflate")
退
tuì
to retreat; to withdraw
堂
táng
(main) hall
鼓
gǔ
drum