collapse, collapsing, collapsed, collapses, to fall down, fall down
Mnemonic
[t-] Tarzan is in [1] front of the [-a] auditorium, where he is camping out for tickets. He built a little structure made of 羽 feathers and 土 soil and lives inside it while wearing a 冂 hood, waiting for the tickets to go on sale. Suddenly it 塌 collapses all over him while he is inside it. He emerges from the wreckage, with 二 two羽 feathers covered in 土 soil sticking out of his 冂 hood.