【正确答案】How to make learning interesting challenged teachers long before the current crisis. Another problem was how to show students certain things that could not be explained in other ways. Then came virtual reality (VR), a technology that can provide immersive experiences for students. VR lets students experience concepts, processes and skills over and over again until they master the subject. A well-built VR educational system can accommodate all learning stages while helping students get more out of the learning experiences.

【答案解析】1. 该段第一句为翻译难点。“早在……之前”翻译成long before。句子的主语是how引导的句子。2. 该段第三句为翻译难点。“这是一种可为学生提供沉浸式体验的技术”说的是VR技术，因此，翻译时把这一句作为VR的同位语，前半句灵活使用倒装句then came virtual reality。