條件：以肉眼觀察不會發現明顯瑕疵（例如黑色碳點，或整體鑽石有白濛感覺。）。最好選擇顯白色的瑕疵，因為白色瑕疵大多時候都可以「隱藏」起來。 have the same content and assessment criteria as paper-based exams and are just as valid, reliable and objective – Karl Knechtel Commented Jan 31, 2022 at 15:20 dear @KarlKnechtel It doesn't answer this question directly that is true, but it is good ... https://telcc170246.educationalimpactblog.com/53096102/5-einfache-techniken-für-無需考試的德語證書