重点讲解：
1. take risks
冒险；
eg. We do not expect untrained people to take risks.
我们不主张未受过培训的人员去冒险。
eg. His advice to me was to never take risks.
他对我的建议是永远别冒险。
2. rule the roost
当家；作主；主宰；领导；
eg. It's Bill's wife who really rules the roost in that family.
在比尔家里，真正当家的是她的老婆。
eg. Tommy is very bossy;he always wants to rule the roost.
汤米很专横，他总是想一切由他支配。
3. take the lead
领先， 带头；
eg. He is worthy to take the lead.
他是配当领袖的人。
eg. We were just waiting for someone to take the lead.
我们只是在等待某个人来带头。