#include<bits/stdc++.h>
using namespace std;
inline int read()
{
    register int x=0,f=1;
    char c=getchar();
    while(c<'0'||c>'9')
    {
        if(c=='-') f=-1;
        c=getchar();
    }
    while(c>='0'&&c<='9')
    {
        x=(x<<3)+(x<<1)+(c^48); 
        c=getchar();
    }
    return x*f;
}
const int dx[4]={1,-1,0,0};
const int dy[4]={0,0,1,-1};
const int maxn=1005;
bool f[maxn][maxn],vis[maxn][maxn];
int main()
{
	int t=read();
	while(t--)
	{
		bool flag=0;
		queue<pair<int,int> > q;
		int n=read(),top=0;
		q.push(make_pair(1,1));
		vis[1][1]=1;
		while(!q.empty())
		{
			top++;
			if(top<=2*n-2)
			{
				int le=read(),ri=read();
				f[le][ri]=1;
			}
			if(q.front().first==n && q.front().second==n)
			{
				flag=1;
				break;
			}
			for(int i=0;i<4;i++)
			{
				int xx=q.front().first+dx[i],yy=q.front().second+dy[i];
				if(xx<1 || xx>n || yy<1 || yy>n || f[xx][yy]==1 || vis[xx][yy]==1) continue;
				q.push(make_pair(xx,yy));
				vis[xx][yy]=1;
			}
		}
		if(flag) cout<<"Yes\n";
		else cout<<"No\n";
		getchar();
	}
	return 0;
}