$ sudo apt-get update
$ sudo apt-get install fcitx-libpinyin 

fcitx-libpinyin is installed in your system.

Make ensure the fcitx-libpinyin package were installed using the commands given below,

$ sudo dpkg-query -l | grep fcitx-libpinyin *

You will get with fcitx-libpinyin package name, version, architecture and description in a table

fcitx-libpinyin package basic information: