Creating new word to code and translate it

Dear Xibo developers

Thanks your previous response.
My condition is that I create a new word in the php code.
Ex: At display page, I create a “Preview” word next to default layout button. Then I add this new word to default.pot file and output to zh_TW.mo file. But it doesn’t to be translated.
What step I missed???

Thank you for reading.

I moved a post to an existing topic: Adding new words to .mo files