他在大学选择了计算机科学作为专业方向。

He chose computer science as his ___specialization in college.

我的专业是计算机科学，但我选择了人工智能作为我的研究方向。

My major is computer science, but I chose artificial intelligence as my ___specialization.

仙人掌叶子的针状特化结构帮助它们在沙漠中保存水分。

The needle-like ___specialization of cactus leaves helps them conserve water in the desert.