いぬ
dog
inu
JMdict 1258330
いぬ犬dogはかしこい賢いsmart
は (topic) raises 犬いぬ (dog) as the topic — “as for dogs…”. The i-adjective 賢いかしこい (smart) then acts as the whole predicate; in plain speech it needs no です (is) after it, so the sentence simply ends on the adjective and sounds casual.
hanamaru