Successful completion
From my interpretation of English "Successful completion", it seems to mean that the requirements for year 1 of a Taiwanese University must be fulfilled. Meanwhile, there must be some core subjects to be completed on each bachelor year in order to be graduated. Say, to complete a Finance degee, I must complete "Intro to Finance I" in year 1 first sem and "Intermediate Accounting" in either year 2 sem 1 or year 2 sem 2. That's the requirement.
So "y1既必修一定要讀晒,唔比停修" is true. You better check on your Taiwanese University's Year 1 syllabus so that the CORE SUBJECTS are to be completed in year 1.