It's up to... 由……来决定
用法透视
"to"后面接代词宾格或名词，表示“由……来做决定；取决于……；是……的职责”。
支持范例
1. Do you want to eat a Western or Chinese meal? It's up to you.
吃西餐还是中餐？由你来决定。
2. It's up to us to help those in need.
我们有责任帮助那些有困难的人。
3. It's not up to you to tell me how to do my job.
用不着你来告诉我怎样做我自己的工作。
会话记忆
A: I'm looking forward to our son's graduation this weekend.
我盼着这个周末儿子毕业呢。
B: Yes. So am I. But what will he do after graduation? He really needs to go to college.
我也是。不过他毕业后做什么呢？他需要上大学。
A: Well, dear, we can't force him to go to college. It's up to him.
可是亲爱的，我们不能强迫他上大学啊，这得由他决定。
B: I know that but he has to learn to be independent. He can't just keep living at home.
我知道，但他得学会自立，他不能老待在家里。