1. It depends on the writing of horizontal batch. If the horizontal batch is written from right to left, the bottom couplet should be posted on the left. 2. If the horizontal batch is written from right to left, the bottom line is pasted on the right. The way to distinguish the upper and lower couplets: the parallel method: look at the last word of the couplet, the last word of the upper couplet is three tones and four tones (flat tone), and the last word of the lower couplet is one tone and two tones (flat tone).