When communicating in Chinese you may often make mistakes using Chinese grammar like:

False:

    妈妈比五年前旧多了。

    Māmɑ bǐ wǔ nián qián jiù duō le

True:

    妈妈比五年前老多了。

    Māmɑ bǐ wǔ nián qián lǎo duō le

 

英语可以把“旧”和“老”都议成old，但是汉语的“旧”是用来指事物经过长时间或经过使用而发生变化。原句说的是妈妈年岁大了，不能用“旧”，要用“老”。

旧 and 老 are all translated into “old” in English. But 旧 in Chinese only indicates that things have changed after being used for a long time. The present sentence speaks of advancement in age, thus 老 rather than 旧 should be used.