is it possible for english teacher to use english without mother tongue everytime he/ she teach?

may be, because not all students can understand what the teacher explained by using the English language, for example just in my class, not all students can understand what thelecturer explained by using English, sometimes mixing English lecturer with the Indonesianstudents to be to understand.

which one is better english taught by native speaker or english teacher

I prefer teaching in up to her by teachers teaching English because more can I receive with that in mind saya.Materi also been appropriate to say that my teaching harapakan, and materials in my terapakan samapaikan easier. Than in my teaching in conveyed by the original teacher of English and sometimes I'm hard to catch his material.