#include <cstdio>
#include <algorithm>
#include <vector>
#include <iostream>
#include <cassert>
#include <string>
#include <string.h>
#include <cmath>
#include <set>
#include <map>
#include <bitset>
#include <iomanip>

#define X first
#define Y second
#define mp make_pair
#define pb push_back

typedef long long ll;

using namespace std;

int sumn = 0;

void solve() {
    int n, m;
    cin>>n>>m;
    sumn += n;
    assert(1 <= n && n <= 100);
    assert(m <= n*(n - 1) / 2 );
    if (n == 3 && m == 3) {
        cout<<"1 2\n";
        cout<<"1 3\n";
        cout<<"3 2\n";
        return ;
    }
    if (m < n || m > 2*n - 4) {
        cout<<"-1 -1\n";
        return ;
    }

    int base = n - (m - n);
    for (int i = 1; i < base; i++) {
        cout<<i<<" "<<i + 1<<"\n";
    }
    cout<<1<<" "<<base<<"\n";
    int lst = base;
    while (lst < n) {
        lst++;
        cout<<1<<" "<<lst<<"\n";
        cout<<lst<<" "<<3<<"\n";
    }
}


int main() {
    int test;
    cin>>test;
    assert(1 <= test && test <= 1000);
    while (test--) {
        solve();
    }
    assert(sumn <= 1000);
    return 0;
}