Say in Japanese!

My boss recently tell me that "Say in Japanese!, Explain in Japanese!", when I can not find the word to explain what I want to say. He knows that I can not explain in English, although I want to say something. Of course he does not know Japanese, so he teases me.
Sometimes it makes me fun and relax and I can find the word to explain, but sometimes sad or annoying.
Life is always like that, that is to say the both sides are there.