英语四级常用连接词可分为以下几类，结合多个权威来源整理如下：
一、时间关系连接词
时间状语从句 - 时间点：
at first, at last, at the beginning, finally
- 时间间隔：after, shortly, subsequently, eventually
- 时间对比：before, whereas, while
- 频率：frequently, regularly, occasionally
时间副词 - 立即：right away, immediately
- 现在：right now, at present
- 未来：soon, subsequently
二、空间关系连接词
位置描述
- 上下：above, below, beneath
- 前后：in front of, behind, to the left/right
- 靠近：close to, nearby, adjacent
方向与范围
- 四处：around, throughout
- 范围：within, outside
三、条件关系连接词
充分条件
- if, provided that, assuming
- 例外：unless, even though
结果与结论
- 因此：therefore, hence, consequently
- 相反：however, nonetheless
四、让步关系连接词
承认对比
- 尽管：though, although
- 即使：even if, even though
五、并列关系连接词
平级连接
- and, but, or, nor
- 因果：because, since
- 转折：however, yet
递进与补充
- not only...but also, furthermore, similarly
六、举例说明
时间关系： "She arrived before
空间关系：
"The library is next tothe park"（位置描述）
条件关系：
"If you finish the homework, you can watch TV"（充分条件）
让步关系：
"The movie was boring, thoughI had high expectations"（承认对比）
七、注意事项
语法功能：连接词不可单独成句，需连接词与从句/短语搭配使用
特殊场景：
whether 引导主语从句时不可用 if（如表语从句、介词宾语等）
用 "such as" 举例时需搭配 "namely" 补充完整
建议结合具体语境选择合适的连接词，并通过练习巩固用法。