My diary

In 2 hours I'll go to work. I teach Arabic in a secondary school. Sometimes, my job can be difficult because the children are  naughty.

I had to guess the word naughty because I wasn't sure what you meant by changeable. You could possibly say unruly, difficult to manage, uncontrollable, or disobedient.

My diary

After 2 hours, I'll go to my<a class="zbobxgzmal" title="Click to Continue > by PhraseFinder" href="#32628004"> work</a> . I teach Arabic language in a Secondry School . My work is difficult becasue of the teenagers studying in my class. They are sometimes uncontrollable.