Is it okay not to put the article "an" before "unbeatable"?
Native speaker’s answer
Rebecca
In this case both are fine. By saying "an unstoppable spirit and an unbeatable energy", the sentence sounds a bit more formal. Repeating the article is not necessary but it does help to add emphasis. While not using the article here is fine, it is not a hard rule that you do not need to repeat an article. It is dependent on the sentence and the context. Ex: I need some who is an effective communicator, team player and leader to fulfill the role. (Repetition of the article is not necessary.) Ex: I need an apple, an orange and a kiwi for the fruit salad. (You need to use the article before each item).