大多数蝙蝠靠回声定位来飞行。Most bats navigate by echolocation.她在山顶上大声喊着,然后聆听着回声.She shouted on the mountaintop and listened for the echo.蝙蝠用一种回声测定法来判断距离.The bat judges distances by a kind of echo - location....
你没把门闩插上，所以狗跑了。You left the latch off the gate and the dog escaped.“海伦走之前吃了点儿东西，”塞西尔急忙插了一句。"Helen had something to eat before she left," put in Cecil anxiously.她说话间，我把水壶灌满并插上了电源。I filled the kettle while she was talking a...