Reception placecards

I'm not quite sure what etiquette says on the matter. But when you fill out the reception placecards that tell your guests what tables they will be sitting at, would you do a single couple as one placecard 'Mr. John Smith and Ms. Molly Brown' or does each person get his/her own i.e. 'Mr. John Smith' and then another card for 'Ms. Molly Brown'??

Please help.
Thanks!

the couple gets 1 card for the 2 of them

Ms. Jane Smith and Mr. John Doe
Table 3

Thanks, you're always so helpful!