What is the nicest way to say "old person" while still being polite and non-offensive? [duplicate]

Almost every language has polite ways to say that someone is old and that someone is getting ones. Are they usual in English? If so, which is the most usual euphemism in English to express these two ideas nowadays? Below are the ones I am familiar with:

to be old

• He is advanced in age.
• He is advanced in years.
• He is of advanced age. (less usual)

to get old

• Aunt Betty is getting along in years

One such idiom is along in years:

Definition: Someone who is old, growing old, or elderly.

The idiomatic expression along in years refers to someone who is old or elderly. Native English speakers use it as a euphemism to illustrate that someone is growing older.

When used in this context, the verb getting often precedes the phrase.
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This idiom can be used to describe people or animals.