Yes, "last-known address" is hyphenated. The hyphen is used to connect the words "last" and "known" to clarify that they collectively describe the noun "address." This hyphenation helps to avoid confusion about the meaning of the phrase.
It is not hyphenated.
Motorcycle is not hyphenated
No it's not hyphenated.
words are only hyphenated when they have a separate meaning when separated than they do when hyphenated
It can be. Some words can be seen both hyphenated and non-hyphenated.
Yes it should be hyphenated.
No, "hardworking" is not hyphenated.
No. Well above is not hyphenated.
peace of mind is not hyphenated.
No, "homework" shouldn't be hyphenated.
Yes it should be hyphenated.
No they shouldn't be hyphenated.