In British English, the adjective elder is usually only used to describe brothers and sisters. ...her elder sister. You use older to talk about the age of other people or things. Elder cannot be followed by than but older can be. I've got a sister who is older than me. Do not confuse elder and elderly. If you describe someone as elderly, you mean that they are old, but this is a slightly more polite word than 'old'. 'The elderly' are elderly people.

英国英语中形容词 elder 通常只用来指哥哥、姐姐，如，her elder sister (她姐姐)。older用于指年龄。elder 后不能接 than，而 older 则可以。例如，I've got a sister who is older than me (我有个姐姐)。不要混淆 elder 和 elderly。elderly意为“年老的”，但比用 old 稍显礼貌一点。the elderly 指老年人。