hammer意思是"捶打、敲打"，home意思是"家"，hammer it home字面意思是「捶打到家了」，可以理解為「話都說到家了"，也就是將事情解釋得再清楚不過了。
看看老外聊天時怎麼用hammer home:
A Is he still going to do it？
B I don't know.I've been trying to hammer home to him that he can't just swim across the Gulf of Mexico.
A他還是要去嗎？
B不知道。我一直努力跟他解釋說泳渡墨西哥灣不是他隨便就能做的。
hammer home例句精選：
John hammers their financial difficulties home whenever his wife suggests they buy something new.
每當妻子建議他們買些新東西時，約翰就盡力向她解釋他們目前的經濟困境。
He needs to hammer home the fact that she was cleared of all charges before the election began.
他需要強調一個事實，即在選舉開始前，她已被免除所有指控。
The boss hopes to hammer the firm's poor financial position home to the staff.
老闆希望把公司糟糕的財務狀況向員工講清楚。
I tried to hammer home to Anne the fact that she would have to get a job.
我試圖讓安妮明白她必須找份工作。
解釋得盡善盡美，希望得到他人的理解。
shed some light提供解釋
We're expecting the new research to shed some light on animal suicides.
我們期待這個新研究可以為動物自殺行為提供一些解釋。
Break it down. 用白話解釋。
If you don't understand what I meant，l'd be happy to break it down for you.
如果你不懂我剛才說的，我很樂意為你詳細說明。