summer and winter

a supplementary-weft unit weave with two tie-down ends and a plain-weave ground cloth. The ratio of tie-down ends to pattern ends is 1:1; there are four ends in each unit; each block requires one pattern shaft; the tie-down ends are the first and fourth ends in the unit; the tie-down ends interlace with the pattern weft in plain weave order. One unit of Block A is 1-3-2-3.