Your sentences are theoretically correct, Rajeev, but I’ll make two points: 1. Even when grammatically correct, we usually avoid using a verb ending in -ing to govern another verb ending in -ing. This is true even if one were a participle and the other a gerund — it just “sounds” weird. In your example, they're both participles. (Note that using multiple -ing forms in parallel is another matter: He likes walking and eating. 2. “Cake” is usually uncountable when referring to the amount one normally eats. If we wish to count, we would say pieces or servings of cake. If you use the plural of “cake,” it means at least two entire cakes, which far more than anyone should eat at once. Recommendation: He is walking and eating cake (or “a cake,” if he does indeed have an entire cake).