Lie down on your couch and scoot around until your back is onthecushions and your legs are resting onthe seat back, at a 90 degree Angle to your waist.
躺在沙发上，后背靠着坐垫，腿搁在椅背上，保持到腰90度的角度。
2
The old man lay propped up oncushions.
老人靠在垫子上躺着。
《牛津词典》
3
They tenderly lifted Toad into the motor-car and propped him up with soft cushions, and proceeded on their way.