I would like to conclude by thanking you all for attending.

conclude 是动词，由前缀 con-（表示"完全、一起"）和词根 -clude（来自拉丁语 claudere，意为"关闭"）组成，字面意思是"完全关闭"，引申为"结束、得出结论"。在句中表示"结束发言"的动作。