Qt Sanity Bot Warning: Increasing file size by more than 50%

Recently, I lupdated the out-of-date qtcreator_zh_TW.ts file, and then push to Gerrit for review. However, there is a Warning Message of Qt Sanity Bot showed up:

Warning: Increasing file size by more than 50% (1067KiB => 2991KiB)

Review Request: l10n(zh_TW): lupdate qtcreator_zh_TW.ts

Can someone in Qt Team teach/tell me what should I do to solve this problem?

If possible, please describe specifically.