Their is a triangular shelf support in the middle of the shelf (underneath it) that would be in the way of anything in the middle up to ten inches below the shelf.
(Their; is; a triangular shelf support in the middle of the shelf (underneath it) that would be in the way of anything in the middle up to ten inches below the shelf) (that; would be; in the way of anything in the middle up to ten inches below the shelf)
Their that
is would be
a triangular shelf support in the middle of the shelf (underneath it) that would be in the way of anything in the middle up to ten inches below the shelf
in the way of anything in the middle up to ten inches below the shelf