During the meeting, she accidentally put her foot in her mouth by mentioning the failed project.

put 是动词，意思是"放置"或"使处于某种状态"。 her 是代词 she 的所有格形式，意思是"她的"。 foot 是名词，意思是"脚"。 in 是介词，表示"在...里面"或"进入"。 mouth 是名词，意思是"嘴"。 put one's foot in one's mouth 是一个英语习语，字面意思是"把脚放进嘴里"，实际表示"说错话"或"失言"的意思。