import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        Scanner scn=new Scanner(System.in);
        int q=scn.nextInt();
        while(q-->0)
            {
                        int n=scn.nextInt();

                   
            for(int i=0;i<n;i++)
                {
                int x=scn.nextInt();
                int y=scn.nextInt();
                
        }
            System.out.println("YES");
            
    }
    }
}