Regulations Governing Licences and Ratings for Airmen Article 74

The privilege of the holder of private pilot licence-glider includes acting as pilot-in-command to engage in certified glider operation of non-revenue flights.
中文原文 航空人員檢定給證管理規則第74條
經檢定合格之滑翔機自用駕駛員得駕駛經檢定合格之滑翔機及擔任機長作非營業性之飛航。

English translation for reference only; the Chinese text prevails. Not legal advice.