over one's head

A: All these things you cover are way over my head!

B: What don't you understand?

over one's head
超过某人所能理解的

A: All these things you cover are way over my head!
A: 你所讲的这一切都远超过我所能理解的。

B: What don't you understand?
B: 你哪个地方不懂？

"cover" 在这里是讲道理(课程、考试等)所含括的范围。"例句中 "way over my head" 的 "way" 是美语中常用来「强调」程度的字。好象: "This shirt is way too big for me." 这件衬衫我来穿实在太大了。