Within ACL 4.0 and 4.2, horizontal (ACL 4.0) and vertical (ACL 4.2) stripes are not as good at differentiating between the modes as the checkerboard is for ACL 4.4. The vertical stripe in ACL 4.2 is a bit awkward because it emerges out of a failed attempt to do the checkerboard pattern. The first row of alternating colours in the checkerboard pattern emerges into vertical stripes in the 2nd row. The 2nd row starts the vertical stripes that might be followed until all of the space is filled or stopped when they notice that theirs does not look like the sample.
While doing an activity, the working surface is flat, but the person can usually find the back of the working surface by turning the material object over, i.e. turn the paper over.
When horizontal and vertical lines are combined into a grid, they do make errors that they cannot correct on notecards. Drawing the lines on the grid for them compensates for this problem.
