map function in React-Native

I am new to React Native and I am using Typescript for my project. I am difficulty to do mapping in React Native. Below is my code for interface:

interface Teacher {
  name: string;
  sex: string;
  age: number;
  student: Student[];
}

interface Student {
  name: string;
  sex: string;
  address: string;
}

I don't have any problem mapping Teacher's interface but I am having difficulty on how to map Student interface when I use the map function in my code.

{Class.map(class => (
   <View>
      {class.student.map(class => (
          <Text>{class.name}</Text>
      ))}
      {class.student.map(class => (
          <Text>{class.sex}</Text>
      ))}
      {class.student.map(class => (
          <Text>{class.address}</Text>
      ))}
   </View>
)}

When I did my coding like this, I get an error Cannot read property 'map' of undefined in my console. Thank you in advance.