Final answer:
The underlined part, 'I look forward to seeing you,' is an example of an introductory phrase expressing anticipation or excitement about a future event or action.
Step-by-step explanation:
The underlined part, I look forward to seeing you, is an example of an introductory phrase.
It is used to express anticipation or excitement about a future event or action. In this case, it shows the writer's enthusiasm about seeing the person they are addressing. Introductory phrases like this one are commonly used in written and spoken English to set the tone or convey the speaker's emotions.