The lesson focused on using previously learned vocabulary to construct sentences and questions in Mandarin, with special emphasis on the characters 幾 (jǐ), meaning “how many,” and 谁 (shuí), meaning “who.” The instructor clarified how these characters are used in sentence structures typical to Mandarin, such as “这个人是谁” (Zhège rén shì shuí) for “Who is this person?” and highlighted differences from English sentence formation. Additionally, the lesson included practical examples like “那个人是我的朋友” (Nàgè rén shì wǒ de péngyǒu), translating to “That person is my friend,” to reinforce learning.