我无法想象更可怕的事情。

I cannot ___conceive of anything more horrible.

你无法想象除了你所知之外的任何存在方式。

You cannot ___conceive of any other way of existence than the one you know.

很难想象这样一个复杂问题的解决方案。

It is difficult to ___conceive of a solution to such a complex problem.