#include <bits/stdc++.h>
using namespace std;
using li = long long;
using ld = long double;
using pii = pair<int, int>;
const int INF = 1e9 + 13;
const int N = 2e5 + 13;
const int M = 1e9 + 7;
const int B = 600;
const int A = 256;
const ld e = 1e-8;
const int LOGN = 20;
mt19937 rnd(time(0));
void solve() {
  int n, m;
  cin >> n >> m;
  vector<bool> a(n, false);
  for (int i = 0; i < m; i++) {
    int x, y, z;
    cin >> x >> y >> z;
    y--;
    a[y] = true;
  }
  int v = -1;
  for (int i = 0; i < n; i++)
    if (!a[i]) v = i;
  for (int i = 0; i < n; i++) {
    if (i != v) cout << v + 1 << ' ' << i + 1 << '\n';
  }
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t = 1;
  cin >> t;
  while (t--) solve();
}
