【解析】
这篇作文主要写清楚老师学生对高考做的准备工作，说明老师对学生的认真，学生的努力，用一般现在时，同时应该对现象提出解决办法。写作时要用一些固定结构，象with the college entrance examination approaching, are engaged in preparing for ，are devoted to giving us lessons some of them even stay up late into deep night, which makes them feel sleepy in class. Some of them even stay up late into deep night, which makes them feel sleepy in class.这句话是非限制性定语从句。
