#include<bits/stdc++.h>
using namespace std;
const int N=3e5+10;
int a[N],b[N],q[N],p[N],tag[N];
int T,n;
bool cmp1(int x,int y){
	return a[x]<a[y];
}
bool cmp2(int x,int y){
	return b[x]<b[y];
}
int main(){
	scanf("%d",&T);
	while (T--){
		scanf("%d",&n);
		for (int i=1;i<=n*3;i++){
			scanf("%d%d",&a[i],&b[i]);
			q[i]=i; p[i]=i;
		}
		sort(q+1,q+n*3+1,cmp1);
		sort(p+1,p+n*3+1,cmp2);
		for (int i=1;i<=n*3;i++) tag[i]=0;
		vector<pair<int,pair<int,int>>>ans;
		priority_queue<int,vector<int>,decltype(&cmp2)>qp(cmp2);
		int id=1;
		for (int i=1;i<=n*3;i++){
			if (tag[p[i]]) continue;
			tag[p[i]]=1;
			pair<int,int>w;
			for (;id<=n*3&&a[q[id]]<=b[p[i]];id++){
				if (tag[q[id]]) continue;
				qp.push(q[id]);
			}
			int sum=2;
			while (!qp.empty()&&sum){
				int t=qp.top(); qp.pop();
				if (tag[t]) continue;
				tag[t]=1;
				if (sum==2) w.first=t; else w.second=t;
				sum--;
			}
			if (sum) break;
			ans.push_back(make_pair(p[i],w));
		} 
		if (ans.size()==n){
			puts("Yes");
			for (int i=0;i<ans.size();i++) printf("%d %d %d\n",ans[i].first,ans[i].second.first,ans[i].second.second);
		}else puts("No");
	}
}