#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int q;
    cin>>q;
    while(q--)
        {
        int n;
        cin>>n;
        while(n--)
            {
            int x,y;
            cin>>x>>y;
        }
        cout<<"YES\n";
    }
    return 0;
}