英语说it’s difficult to do sth肯定是对的。如：

It’s difficult to describe how I feel. 很难描述我的感受。

It’s difficult to understand anything he says. 要理解他说的话很困难。

It’s difficult to get into a university nowadays. 如今进大学读书是难事。

但是，英语可以说It’s difficult doing sth吗？比如英语可以这样说吗？

It’s difficult describing how I feel. 很难描述我的感受。

It’s difficult understanding anything he says. 要理解他说的话很困难。

It’s difficult getting into a university nowadays. 如今进大学读书是难事。