You read a short story and are asked to explain how the author creates suspense. how should you start?

You should start by looking at the words, setting, and tone. If the scene is a dark night by a castle, that already gives you a feeling of mystery. If the author were to use such words as 'silence', 'unknown', and 'hesitantly' these would create suspense in the reader. Once the setting is identified, the rest comes easy.