his family would have filed a report by now.他家人肯定已经报案了

file a report 提交报告

If you file a report, things could get a lot worse for me.

你报告上去事情对我而言会变得更糟。

by now到如今； 至此

The building must have been built up by now.

那幢大楼此时一定已经建成。

Her secret remains untold by now.

她的秘密至今仍未透露。

I'm assuming that you have called him and tried to text him.我猜你电话也打过,短信也发过了

assume用法：

1、assume与presume都有“假定”的意思，但是前者只是一种假设，后者是认定是正确的，真实的，

在等待被认定；

2、assume后常接that，而presume后不接that。

I assume that you can do it.

我假定你能做。

I presume you can do it.

我认定你能做。

相关短语:

assume an air of装出 ... 的样子

He playfully assumed an air of indifference.

他开玩笑地装出一副漠不关心的样子。

She assumed an air of injured innocence.

她装出一副无辜受累的样子。