Collins Chinese Dictionary Plus (3rd edition), 2011:
[+ husband, president etc] 前任的 qiánrèn de
He's a former army officer. 他是位前任军(軍)官。 Tā shì wèi qiánrèn jūnguān.
(=earlier) [+ power, authority] 以前的 yǐqián de
They have lost much of their former authority. 他们(們)失去了许(許)多以前的权(權)力。 Tāmen shīqùle xǔduō yǐqián de quánlì.
▶ the former 前者 qiánzhě
The former believe in a strong centralized government. 前者信仰强(強)有力的中央集权(權)制的政府。 Qiánzhě xìnyǎng qiáng yǒulì de zhōngyāng jíquánzhì de zhèngfǔ.
in former times/years 以前 yǐqián
请勿将 former 和 previous 混淆。former 是指某人曾经拥有的某个特定的工作、职位或角色，或者指某个曾经存在，但现已消失的状况。 …former President Bill Clinton…He murdered his former wife.previous 用来指先前，即说话前所发生的事情或存在的事物。She has a teenage daughter from a previous marriage…Crime increased in 2001 compared with the previous year.