How to choose the healthiest salad greens<br>Look for low-calorie greens. If your idea of healthy is synonymous with low in calories, you might choose red leaf lettuce. This lettuce, like all varieties of lettuce, is mostly water.
Purple leaf lettuce is low in calories.
The context says red leaf lettuce is low in calories but doesn't say anything about purple leaf lettuce.
( z1 low :ARG1 ( z2 lettuce :mod ( z3 leaf :ARG1-of ( z4 purple ) ) ) :ARG2 ( z5 calorie ) )