#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;
    long long int count_sort[1000000];
    long long int count_sort1[1000000];
        int a[1000000][2];
int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */  
    
    int t_cases;

 cin>>t_cases;
    while(t_cases-->0)
    {
       memset(count_sort,0,sizeof(count_sort));
    memset(count_sort1,0,sizeof(count_sort1));
        long long int n;
       cin>>n;
     long long int i;
     int j;

     for(i=0;i<n;i++)
     {
         for(j=0;j<2;j++)
       {
       cin>>a[i][j] ;   
       }
     }
      //  cout<<"iam here"<<endl;
    for(i=0;i<n;i++)
    {
        count_sort[(a[i][0])+1000]=count_sort[(a[i][0])+1000]+1;
        count_sort1[(a[i][1])+1000]=count_sort1[(a[i][1])+1000]+1;
    }
//cout<<"iam here_again"<<endl;
     int flag=1;
      for(i=0;i<1000000;i++)
    {
       if(count_sort[i]%2!=0 || count_sort1[i]%2!=0)
       {
           flag=0;
           break;
       
       }
    }

        if(flag==0)
        cout<<"NO"<<endl;
     else
       cout<<"YES"<<endl;           
      
    }

    
    
    return 0;
}