#define _USE_MATH_DEFINES
#include<iostream>
#include<fstream>
#include<string>
#include<vector>
#include<utility>
#include<algorithm>
#include<climits>
#include<set>
#include<map>
#include<cmath>
#include<iomanip>
#include<iterator>
#include<queue>
#include<stack>
#include<cctype>
#include<deque>
#include<time.h>
#include<bitset>
#include<random>
#include<unordered_set>
#include<unordered_map>
#include<sstream>
#include<random>
#include<numeric>
#include <assert.h>

#pragma warning(disable : 4996)

#pragma comment(linker, "/STACK:16777216")

#define en "\n"
#define forn(i, n) for(int i = 0; i < n; i++)
#define all(x) (x).begin(), (x).end()
#define allr(x) (x).rbegin(), (x).rend()
#define pb push_back
#define pii pair<int, int>
#pragma warning(disable : 4996)
#define fst first
#define snd second
typedef long long ll;
typedef long double ld;

using namespace std;


template<typename T> void print(vector<T>& a)
{
	for (int i = 0; i < a.size(); i++)
		cout << a[i] << ' ';
	cout << en;
}

template<typename T> void print(deque<T>& a)
{
	for (int i = 0; i < a.size(); i++)
		cout << a[i] << ' ';
	cout << en;
}

template<typename T> void print(vector<vector<T>>& a)
{
	for (int i = 0; i < a.size(); i++)
	{
		for (int j = 0; j < a[i].size(); j++)
			cout << a[i][j];
		cout << en;
	}
}

template <typename T> void input(vector<T>& a)
{
	for (int i = 0; i < a.size(); i++)
		cin >> a[i];
}

template<typename T> void input(deque<T>& a)
{
	for (int i = 0; i < a.size(); i++)
		cin >> a[i];
}

template<typename T> void input(vector<vector<T>>& a)
{
	for (int i = 0; i < a.size(); i++)
		for (int j = 0; j < a[i].size(); j++)
			cin >> a[i][j];
}

const ll INF = 1e9 + 5;
const ll MOD = 1e9 + 7;
const int N = 5e5 + 10;
const double EPS = 1e-10;

int j = 0;
void solve() {
	int n, m;
	cin >> n >> m;
	//cout << j++ << " " << n << " " << m << en;
	vector<pii> a(m);
	for (auto &to : a) {
		cin >> to.first >> to.second;
		swap(to.first, to.second);
	}

	sort(all(a));
	if (a.size() % 2 == 1) {
		cout << "No" << en;
		return;
	}
	
	for (int i = 0; i < a.size(); i += 2) {
		if (i + 2 < m && a[i + 1].first == a[i + 2].first) {
			cout << "No" << en;
			return;
		}
		int delta = a[i + 1].first - a[i].first;
		if (a[i + 1].second == a[i].second && delta % 2 == 0){
			cout << "No" << en;
			return;
		}
		if (a[i + 1].second != a[i].second && delta % 2 != 0) {
			cout << "No" << en;
			return;
		}
	}
	cout << "Yes" << en;
}

/* stuff you should look for
	* int overflow, array boundsк
	* special cases (n=1?)
	* do smth instead of nothing and stay organized
	* WRITE STUFF DOWN
	* DON'T GET STUCK ON ONE APPROACH
*/

int main() {
	srand(time(0));
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cout.setf(ios::fixed);
	cout.precision(2);
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
#endif
	int t = 1;
	cin >> t;
	while (t--) {
		solve();
	}
}