复杂得 complex, complicated, sophisticated, intricate, tricky

a complex argument/problem/subject

复杂难懂得论证 / 问题 / 科目

The instructions look very complicated.

这说明书看起来很复杂难懂。

Medical techniques are becoming more sophisticated all the time.

医疗技术日益精妙复杂。

Medicine is a complex subject, since medical techniques are becoming more sophisticated all the time and the operation of the equipment is increasingly complicated.

医学是一门复杂难懂得学科，因为医疗技术越来越精妙复杂，设备得操作也越来越复杂难懂。

an intricate interpersonal network

一个错综复杂得人际关系网络

Dealing with an intricate interpersonal network is a tricky business.

应付错综复杂得人际关系网络是一件复杂难办得事情。