This is a modular pattern made entirely out of one size triangle that you knit and join. Can be made accumulatively where the pattern grows from one garment into another as triangles are added.

Knit two triangles and join to make a Hood - Construction No. 4A.
Add triangles to Hood to make a Shrug - Construction No.4B.
Add triangles to Shrug to make a Bolero - Construction No 4C.
Add triangles to Bolero to make Sweater- Construction No 4D.