"We drink the juice."
Translation:אנחנו שותות את המיץ.
No, not anything definite. It has to be "definite direct object" in order to have ה. There is also indefinite object, and then you never include את. It also goes for סמיכות. It is just a regular noun, which can be either a subject, or a direct or an indirect object. So, not every time there is סמיכות.