表列举：for example,for instance,such as表补充：besides,in addition,moreover…表对比：on the one hand… on the other hand,while…1.表原因：because of,thanks to,due to ,owing to…表结果：therefore,thus... 表列举：for example,for instance,such as表补充：besides,in addition,moreover…表对比：on the one hand… on the other hand,while…1.表原因：because of,thanks to,due to ,owing to…表结果：therefore,thus...