The biggest characteristic of an unsustainable rebound is that the volume doesn't keep up. This wave of rebound lasting four or five days, the index is moving up, but the trading volume shrinks every day. Compared to the previous bull market rally, it's clear from the chart that continuous upward movement always comes with increasing trading volume. What's an even worse rebound? It's when key stocks like leading optical stocks, domestic chip leaders, and newly listed storage leaders show increased volume while the market is shrinking, but their prices don't rise. Think about it.