My playlist to learn prepositions (R. Murphy "English Grammar in Use self-study reference and practice book for intermediate learners of English". Units 124-127)
https://www.youtube.com/playlist?list=PLPdaDDo0ag53gCyzvVZw5WOA1j5rzw_nr
https://www.youtube.com/playlist?list=PLPdaDDo0ag53gCyzvVZw5WOA1j5rzw_nr