连词是连接词语、短语或句子的重要工具，包括"and"表示并列关系，"but"表示转折关系，"or"表示选择关系，"so"表示因果关系。掌握这些连词的用法可以让英语句子更加流畅、清晰。
1. And
"And"表示并列关系，连接两个或多个相同类型的词语、短语或句子。
- I love to read books and watch movies.
- My sister is smart and hardworking.
- She went to the store and bought some milk.
2. But
"But"表示转折关系，在句子中起到对比、否定、反转的作用。
- I want to go to the party, but I have to study for my exam.
- She is a great singer, but she doesn't like performing in public.
- The weather was hot, but the water in the pool was cold.
3. Or
"Or"表示选择关系，在句子中起到提供选项的作用。
- Do you want to go to the beach or the mountains for vacation?
- Should I wear a dress or pants to the party?
- You can have the cake or the ice cream for dessert.
4. So
"So"表示因果关系，在句子中起到原因、结果、推论的作用。
- I studied hard for the exam, so I got an A.
- The movie was scary, so I couldn't sleep that night.
- She is allergic to peanuts, so she can't eat peanut butter.
