go语言接口实现错误 显示student2类型无法解析？

package main
type People interface {
    Speak(string) string
}
type Student2 struct{}

func (stu Stduent2) Speak(think string) (talk string) {
    if think == "帅" {
        talk = "你是个大帅比"
    } else {
        talk = "您好"
    }
    return
}
func main() {
    var peo People = Student2{}
    think := "bitch"
    println(peo.Speak(think))
}

希望输出结果是 你好