shell - 将较短的表格转换为完整的表格

Question

输入文件1：

IT  : Information Technology
B.Tech : Graduation
CS : computer science

输入文件2：

B.Tech has the different groups.
One of several groups is IT and it has CS.
Most of the students are selecting these two groups.

输出应该是这样的：

将输入 file1 的完整形式替换为输入 file2

任何人都可以帮助创建使用 awk/sed 的 shell 脚本...

Answer 1

 awk -F' : ' 'NR==FNR{a[$1]=$2;next}{for(x in a)gsub(x,a[x])}1' file1 file2

输出将是：

kent$  awk -F' : ' 'NR==FNR{a[$1]=$2;next}{for(x in a)gsub(x,a[x])}1' file1 file2
Graduation has the different groups.one of several groups is Information Technologyand it has computer science.Most of the students selecting these two groups.

但是有一个问题需要注意：

递归替换问题

例如：

CS : computer science (CS)

这会发生吗？应该怎么做？