explain sth to sb
to give a reason, or be a reason, for sth
说明(…的)原因；解释(…的)理由
She tried to explain but he wouldn't listen.
她试图说明一下原因,可他根本不听。
Alex explained that his car had broken down.
亚历克斯解释说他的汽车出了毛病。

brave
勇敢的；无畏的
同义词：courageous
brave men and women
英勇无畏的男女
Be brave!
勇敢一些！
I wasn't brave enough to tell her what I thought of her.
我当时没有勇气告诉她我对她的看法。

look after
look after yourself
look after sb
look after sth
(especially BrE) to be responsible for or to take care of sb / sth
对…负责；照料；照顾
Who's going to look after the children while you're away?
你不在时谁来照料小孩？
I'm looking after his affairs while he's in hospital.
他住院时由我处理他的事务。

injured
受伤的；有伤的
an injured leg
受伤的腿
Luckily, she isn't injured.
幸运的是,她没受伤。
Carter is playing in place of the injured O'Reilly.
卡特替代受伤的奥赖利上场比赛。

来源:可可英语 http://www.kekenet.com/video/201704/499621.shtml