连接词前的逗号

在并列复合句中，用并列连词（如 and、but、or、so、yet）连接两个独立分句时，要在连接词前加逗号。

Use a comma before a coordinating conjunction (and, but, or, so, yet) when joining two independent clauses in a compound sentence

学习证据 / Evidence

• 在并列复合句中，要在并列连词前加逗号，例如：“I wanted to go outside, but it was raining”。
• 能区分并列复合句（两个独立分句）和带并列谓语的简单句，例如：“She sang and danced”不需要逗号，而“She sang a song, and he played the piano”需要。
• 能修改文本，在并列复合句中的并列连词前补上缺失的逗号。

• Place a comma before the coordinating conjunction in a compound sentence, e.g. 'I wanted to go outside, but it was raining'
• Distinguish compound sentences (two independent clauses) from simple sentences with compound predicates, e.g. 'She sang and danced' needs no comma but 'She sang a song, and he played the piano' does
• Edit writing to insert missing commas before coordinating conjunctions in compound sentences

评估问题 / Assessment

当{{name}}用像“but”或“so”这样的连接词连接两个完整的想法时——比如“I wanted to go, but it was raining”——{{name}}会在那个连接词前加上逗号吗？

When {{name}} joins two complete thoughts with a word like "but" or "so" — like "I wanted to go, but it was raining" — do they put a comma before that joining word?