All are breeds of dog.

Oak, Poplar, Maple.

All are varieties of trees.

Flat white, long black and instant.

All types of coffee.

Earl Grey, Darjeeling, Lapsang Souchong 

All are types of tea.

Tulip, crocus, daffodil 

All are types of flowers.

Polka dot, plaid, checks.

All are textile patterns.

Camembert, Cheddar and Edam?

All are types of cheese.

Snow White, Cinderella, Beauty and the Beast

All are traditional fairy tale princesses who featured in popular Disney musicals.

Crankpins, Crankshafts and Main bearings.

All are internal-combustion-engine vehicle parts.

Rabbits, Maugrim, the Secret Hill.

All words or names that were changed in the early American editions of The Lion, the Witch and the Wardrobe.

Nimienus, Nausus, Oscuns 

They are dancing fauns from Prince Caspian's Dancing Lawn meeting.

Chlamash, Corradin and Azrooh

They are fierce Calormene Tarkaans from the eastern provinces who fought for Prince Rabadash in The Horse and His Boy.

'Spotty' Sorner, big Bannister and the two loathesome Garrett twins

All members of the Experiment House gang of bullies.

Rogin, Duffle and Bricklethumb. 

All Narnian dwarfs. 

Octesian, Revilian, Restimar. 

All three are part of the Seven Missing Lords who sailed to the East during Miraz's reign. 

Fusilli, Penne & Macaroni