The complete answer would be: / e` come quello di Gloria / As the verb is already in the question, for instance: Come e` questo libro? You don't need to repeat the verb in the answer. It is not colloquial form, it is just the Italian language, where redundancy is not desired (as in probably all languages) and therefore the verb in the answer can be omitted when it is uniquely determined by the verb in the question. === Another example: - com'e` questo piatto (dish) ? - buono (good) OR: - e` buono (it is good, it tastes good)

You're right, this sentence doesn't have a verb at all; yet, it is totally correct. In spoken Italian you can omit a verb in anwering a simple question like "what is your ___ like?" Saying "like Giulia's one". You can find this in informal, or otherwise non-academic writing. For example in a novel you can find a description that goes: "Il quaderno di Giovanni era pieno di appunti. Come quello di GIulia." ("John's notebook was filled up with notes. Like Julia's one.") Anyway it is not a formal or academic contruction. The complete sentence will be "Questo --- è come quello di Giulia". Although you can often omit the subject, you ALWAYS need a verb in Italian. When you will be more familiar with the language you can start using colloquial sentence construction when speeking, but now I advice you to stick with the basics. Spero di esserti stato utile!