Can a joker be used for a single tile or as part of a pair?
No, a joker can never be used for a single tile or as part of a pair. Jokers can only be used in groupings of 3 or more identical tiles. If a grouping on the card is not made up of idencial tiles, then each tile would be considered a single tile (eg, the current year or NEWS). Although these groupings of single tiles may be shown on the card without spaces, it should be remembered that it is not possible to pick up a discard to expose these groupings.