#include <bits/stdc++.h>
using namespace std;

template <typename A, typename B>
string to_string(pair<A, B> p);

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);

string to_string(const string& s) {
	return '"' + s + '"';
}

string to_string(const char* s) {
	return to_string((string) s);
}

string to_string(bool b) {
	return (b ? "true" : "false");
}

string to_string(vector<bool> v) {
	bool first = true;
	string res = "{";
	for (int i = 0; i < static_cast<int>(v.size()); i++) {
		if (!first) {
			res += ", ";
		}
		first = false;
		res += to_string(v[i]);
	}
	res += "}";
	return res;
}

template <size_t N>
string to_string(bitset<N> v) {
	string res = "";
	for (size_t i = 0; i < N; i++) {
		res += static_cast<char>('0' + v[i]);
	}
	return res;
}

template <typename A>
string to_string(A v) {
	bool first = true;
	string res = "{";
	for (const auto &x : v) {
		if (!first) {
			res += ", ";
		}
		first = false;
		res += to_string(x);
	}
	res += "}";
	return res;
}

template <typename A, typename B>
string to_string(pair<A, B> p) {
	return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}

template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
	return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}

template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
	return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}

void debug_out() { cerr << endl; }

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
	cerr << " " << to_string(H);
	debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
#define endl '\n'
#define __ ios_base::sync_with_stdio(0);cin.tie(0);
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(),x.end()
#define forn(i,a,n) for(int i=a; i < n; i++)
typedef long long int lli;
typedef long double Double;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
const int mod = 1e9+7;
const int maxn = 2e5+5;
const int inf = 1e9;

void solve(){
	int n,m;
	cin >> n >> m;
	set<int> arriba,abajo,uni;
	vi eventos;
	for(int i=1; i <=m; i++){
		int r,c;
		cin >> r >> c;
		r--;
		if(r == 0) arriba.insert(c);
		else abajo.insert(c);
		uni.insert(c);
	}

	for(int x : uni)
		eventos.pb(x);
	bool pendiente =  false;
	int row = -1, col = -1;
	while(!eventos.empty()){
		int x = eventos.back();
		eventos.pop_back();
		int lugar = -1;

		if(arriba.count(x) && abajo.count(x)){
			lugar = 2;
		}
		else if(arriba.count(x)){
			lugar = 0;
		}
		else if(abajo.count(x)){
			lugar = 1;
		}
		assert( lugar >= 0);

		if(lugar == 2){
			if(pendiente){
				cout << "NO\n";
				return;
			}
			else{
				pendiente = false;
				row = col = -1;
			}
		}
		else{
			if(pendiente){
				int entre = col - x - 1;
				if(row != lugar){
					//impar
					if(entre%2){
						pendiente = false;
						row = col = -1;
					}
					else{
						cout << "NO\n";
						return;
					}
				}
				else{
					if(entre%2 == 0){
						pendiente = false;
						row = col = -1;
					}
					else{
						cout << "NO\n";
						return;
					}
				}
			}
			else{
				pendiente = true;
				row = lugar;
				col = x;
			}
		}
	}

	if(pendiente) cout << "NO\n";
	else cout << "YES\n";
}

int main(){__
	int t=1;
	cin >> t;
	while(t--){
		solve();
	}
	return 0;
}



