Some people think that the islanders used large strong wooden tools,but there is not
问题描述：
Some people think that the islanders used large strong wooden tools,but there is not
enough evidence to prove.这个句子是什么句,为什么but前面要加逗号呢?它不是连词吗?
答
普通陈述句,but前加逗号,是因为前一句语意完整,而后一句转折陈述.那写作文是加不加逗号有什么要求的吗？另起了一个意思，是一个完整的意群，写作文最好要分开写！