Subject + Verb + 什么?
什么 means "what" and is used in place of the unknown noun in a sentence. It can appear as the object or subject of a verb without changing the sentence structure. For example, 你吃什么? means "What are you eating?" and 这是什么? means "What is this?"
你早饭吃了什么?
nǐ zǎofàn chī le shénme?
What did you have for breakfast?
这是什么?闻起来好香。
zhè shì shénme? wén qǐlái hǎo xiāng.
What is this? It smells so good.
你包里装的是什么?
nǐ bāo lǐ zhuāng de shì shénme?
What's in your bag?