这个问题涉及高度的复杂性。

The problem involves a high level of ___complexity.

这个系统会因其自身的重量和复杂性而崩溃吗？

Will this system collapse under its own weight and ___complexity?

现代技术的复杂性常常让用户不知所措。

The ___complexity of modern technology often overwhelms users.