We can use QQ to talk with each other online.
--Good! Will you please show me it?
A:what to use B:how to use C:when to use D:where to use
网友回答
解析：what to do 后面不加任何东西，因为what可以在从句里充当宾语，what强调“做什么..”；而how/when/where to do 后面要加it，因为how/when/where引导的从句，必须有宾语，从句才完整，how强调“什么方式..”。 how to use it 怎么用QQ，what to use it 中 what 本身就是宾语，再加一个it 就讲不通了。故选B