As a rule of thumb good trend lines should touch at least three previous highs or lows. The more points the line catches, the better the line.

• 实际经验证明,一条可信的市场动向曲线应当至少三次碰到先前的高峰点或低谷点。一条曲线能抓住的接触点越多,这条曲线就越可信。