频
pín
frequency
frequently; repetitious
他最近频繁地出差，家人很担心。
tā zuì jìn pín fán de chū chāi，jiā rén hěn dān xīn。
He has been traveling for work frequently lately, and his family is very worried.
这台机器出现故障的频率越来越高。
zhè tái jī qì chū xiàn gù zhàng de pín lǜ yuè lái yuè gāo。
The frequency at which this machine breaks down is getting higher and higher.