Version 3 of Hiding Under by Eric Eve begins here.
"Allows things to be hidden under other things, using a many-to-one underconcealment relation. Can be used either standalone (with basic functionality) or in conjunction with Underside (to add fuller functionality to both extensions). Version 3 of Hiding Under avoids using phrases deprecated in Version 6E59 of Inform."

• Part 1 - The Underconcealment Relation
• Part 2 - Phrases
• Part 3 - Extensions to Underside (for use with Underside by Eric Eve)
• Part 4 - Standalone Material (for use without Underside by Eric Eve)
• Chapter 1 - Action Definition for Putting Under
• Chapter 2 - Looking Under
• Part 5 - Common Grammar
• Part 6 - Taking something that hides something underneath
• Chapter 1 - Common Material
• Chapter 2 - Additional rule for use with Underside (for use with Underside by Eric Eve)