The canteen gets very busy and noisy at lunchtimes, but we all enjoy chatting to our friend after intensively studying in the classes.

intensively 是形容词 intensive 的副词形式，由 intensive（密集的、加强的）加上副词后缀 -ly 构成。intensive 来自动词 intend（打算、意图）的词根，表示"集中精力、高强度"的意思。 intensively studying 表示"集中精力地学习"或"高强度学习"，强调学习时投入了大量精力和专注度。