上升和下降趨勢(shì)的組合描述（嵌入了時(shí)間和程度之后）：
　　1. 先上升后下降的句型：
　　...... increased slowly during…… and …… but fell sharply in …….
　　A steady fall in …… during …… and …… followed the sharp increase in …….
　　2. 先下降后上升的句型：
　　…… fell before …… began to make a recovery ……
　　…… continue the recovery, climbing to ……
　　…… dropped during …… but increased again in ……
　　…… fell and then pick up during ……
　　…… collapsed before rising to ……at the end of ……
　　3. 起伏波動(dòng)的句型：
　　…… fluctuated sharply all through ……
　　4. 波動(dòng)不大的句型：
　　…… hardly changed through the period between ……and ……
　　柱狀圖形的描述