$ sudo apt-get update
$ sudo apt-get install mythes-en-us 

mythes-en-us is installed in your system.

Make ensure the mythes-en-us package were installed using the commands given below,

$ sudo dpkg-query -l | grep mythes-en-us *

You will get with mythes-en-us package name, version, architecture and description in a table

mythes-en-us package basic information: