Here’s a lively combination that can work, despite the signs’ differences. Shy Cancer’s initiative is boosted by his Sun’s warmth, while Gemini’s sociability may be (depending on her Sun sign) toned down by her background lunar influence. Both these signs are changeable, so they’ll be able to keep up with each other.
Sun in Cancer may be protective and nurturing, but he is still a Cardinal sign. This means he’s likely to make the first move (albeit indirectly). Although he’s initially cautious, once his partner has earned his trust he reveals his emotional core. Sun in Cancer is passionately domestic; his love, anger or neediness is most easily aroused by events that impact his home and family. He’s happiest with a partner who will actively create a nurturing home with him.
Moon in Gemini needs to keep it light. Intense exchanges make her uneasy, because she intellectualizes her emotions. But her partner can be sure that she’s comfortable with him when she discusses (in a detached manner) every detail of her feelings. He must be comfortable with communication, because this is how Moon in Gemini bonds. However, the Shadow side of this sign can drain all the meaning out of emotional exchanges; deeper issues can easily be ignored as she skims the surface with gossip.
Sun in Cancer may be undermined by Gemini’s discomfort with his emotional displays. As he reaches out to give her a hug, she’ll respond with jokes or nervous chatter. Moon in Gemini will feel swamped by Cancer’s flood of nurturing, and slightly panicked by his intensity. But Gemini’s need to chat about everything will blend beautifully with Cancer’s preference for one-on-one bonding. Together, they can create a dynamic, communicative relationship that keeps moving forward. And Cancer’s sensitivity will ensure that at least some of their emotional dynamics will go beyond the superficial (once he realizes that he needs to back off and give Gemini some breathing room).