4:15 in English is "four fifteen". This comes from the way that hours and minutes are typically written in English, with the hour first followed by the minute. Here are some examples of sentences using this time in English:

I will meet you at four fifteen.

The movie starts at four fifteen.

We need to leave by four fifteen.

In Chinese, these sentences would be:

我会在4:15点和你会面。

电影在4:15点开始。

我们必须在4:15点前离开。