n.動力；動因

Listen to the clock. Tick tock, tick tock. 聽這個鐘，滴答，滴答。

Tick, tock, tick tock, what's the time please? 找一名學(xué)生幫老師拿出一面大鐘

Rain, you tick tock, just like a clock. 雨，你滴滴嗒嗒，就像一個鬧鐘。

Tick tock went the clock(on the table). 桌上的鐘表滴答滴答的響著。

Listen to the clock. Tick tock. tick tock. 聽這個鐘。滴答，滴答。