fallen back的用法和樣例：
例句
- Seeing the ball coming his way, the man fell back a pace.
看到球向他飛來，這人後退了一步。 - After touching 143, the price (ie of shares on the stock-market) fell back to 108 by the close of trading.
股票價格攀上143點後，收市時回落到108點。 - The crowd fell back to let the players through.
人群後退讓運動員們通過。 - The crowd fell back to let the ambulance through.
人群往後退，讓救護車通過。
