FOLKS
1) Our neighbours are simple folks.
2) I didn´t have time to write letters to my folks.
3) That´s all for tonight, folks.

SPADES
clubs, diamonds, spades, hearts

MYSTERY
1) It´s a mystery to me how he found it.
2) I got / received a mystery package last night.
3) Who made the record Magical Mystery Tour in 1967? (The Beatles)

COME UP WITH
1) Paul, come up with something!
2) I came up with a good plan but you refused it.
3) It didn´t take her long to come up with a better idea. - nicer English,
or It didn´t take long and she came up with a better idea.