The test passes if after five seconds, in each of the three rows, the red rectangle is in the column at the times indicated. Thus, from the document load until 2s afterwards, the red square in all three rows must be in the left column. At 2s, all three red squares must move to the right column. At 4s, the red square in the first row must move to the left column and the other two red squares must remain in the right column.