英语四级考试涉及的词汇范围非常广泛，以下是一些常见的英语四级单词分类：

1. 基础词汇：
   - 常见动词：study, work, learn, do, make, etc.
   - 常见名词：book, student, school, time, etc.
   - 常见形容词：big, small, good, bad, happy, etc.
   - 常见副词：often, always, never, quickly, slowly, etc.
   - 常见连词：and, but, or, because, etc.

2. 学术词汇：
   - 科学：biology, chemistry, physics, experiment, etc.
   - 经济：economy, market, investment, inflation, etc.
   - 文学：novel, poetry, character, theme, etc.
   - 历史：revolution, civilization, emperor, dynasty, etc.
   - 政治：government, democracy, policy, election, etc.

3. 生活词汇：
   - 食物：food, fruit, vegetable, meat, etc.
   - 交通：car, train, bus, subway, etc.
   - 环境：nature, pollution, climate, environment, etc.
   - 健康：exercise, diet, sleep, stress, etc.
   - 娱乐：music, movie, game, sport, etc.

4. 主题词汇：
   - 教育：education, school, teacher, student, etc.
   - 科技：technology, computer, internet, software, etc.
   - 环保：environmental protection, recycling, renewable energy, etc.
   - 社会：society, community, population, diversity, etc.
   - 体育：sports, fitness, competition, athlete, etc.

以上只是一些常见的英语四级单词，考生可以通过词汇书籍、在线词汇资源以及四级词汇题库来扩充自己的词汇量。同时，通过阅读英文材料、听力练习和口语练习等方式来巩固和运用所学的词汇。