宾语从句 ：即从句（how I can use the computer）做主句（Can you show me） 的宾语
宾语从句主要有一下几种形式,各举一例：
I think that he is a student.(连词that引导)
I don't know where to go.(特殊疑问词where引导)
can you tell me if / whether he can come (if 或whether 引导)