WHOLE CHARACTER
套tào
a cover; a sleeve; a case; to slip over; to encase; a set; a suite; a noose; a trap; to harness; to copy; to apply mechanically
套 means a covering or a set: 手套 'gloves', 套路 'a routine', and 圈套 'a trap'.
ZDIC: 会意,从大、从长 — the modern bottom is the old 'long' piece written in its stretched variant form (镸). The reading cháng is only for that 镸/长 piece itself; it is not a sound of 套. No modern 长 word-reading is taught in this lesson.
TOP: THE PIECE NAMED BY ZDIC
大dà
big; large
A standalone character; kept separate from the unclaimed visual role in 参 and the base-figure role in 天.
In 套: top: the piece named by ZDIC Shown with its documented or clearly limited role.
BOTTOM: THE OLD 'LONG' PIECE (長) IN ITS STRETCHED WRITTEN FORM
镸cháng
the stretched written form of 长 (long)
A written-shape label for the stretched 长 form; a visual piece, not a taught word.
In 套: bottom: the old 'long' piece (長) in its stretched written form The reading cháng is only for the 镸/长 piece itself; it is not a sound of 套. The piece is shown for its written shape, and no modern 长 word-reading is taught in this lesson.