How do you spell "out"?
Prepositions are the service part of speech. What does this mean? And the fact that their meaning is auxiliary, that is, they help to determine the relationship of different parts of speech to each other. However, writing prepositions is often difficult. And how do you spell "from under"?
The main thing that needs to be understood is that “from under” is written only through a hyphen. This is a well-established form, not a combination of two “from” and “under” prepositions. Otherwise, this preposition is not used. As well as the prepositions “over”, “due”.
Any preposition is used with some indirect case. The preposition “from under” is always applied only with a genitive case that answers the questions “to whom? what? For example: "I got out of bed (what?)".