1、He had only to speak one word and his dog would come to heel at once.
他只要叫一聲，他的狗就會立刻跟在他后面。

2、If only he spoke one word, his dog would come to heel at once.
他只要招呼一聲，狗就會立刻跟上來。

3、He refused to come to heel and had to be removed from the class.
他拒絕緊跟在后，不得不被班里開除了。

come to heel翻譯