English learners in Taiwan always tend to tell foreigners that their English is "poor" and "broken". In my view, if they really think that's how they are in terms of learning a language, they will be like that forever. So, I will suggest them use a different expression, for instance, they can say "My English is functional, but not fluent yet." in place of saying "I can't speak English well" or "I am not good in English".
Don't sell yourselves short and be more self-assured.
in terms of 就...而言
in place of 取代
don't sell oneself short 看輕自己