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

struct DSU {
    int n;
    vector<int> fa, siz;

    DSU(int n) : n(n) {
        init(n);
    }

    void init(int n) {
        fa.resize(n);
        iota(fa.begin(), fa.end(), 0);
        siz.assign(n, 1);
    }

    int find(int x) {return (x == fa[x] ? x : fa[x] = find(fa[x]));}

    bool merge(int x, int y) {
        int fx = find(x), fy = find(y);
        if (fx == fy) return false;
        fa[fy] = fx;
        siz[fx] += siz[fy];
        return true;
    }

    bool same(int x, int y) {
        return find(x) == find(y);
    }
};

void solve() {
    int n, m;
    cin >> n >> m;

    const int K = (m + n - 2) / (n - 1);
    vector dsu(K, DSU(n));
    vector e(K, vector(n, vector<int>()));
    for (int i = 0; i < m; ++i) {
        int u, v;
        cin >> u >> v;
        --u, --v;

        int l = 0, r = K - 1;

        while (l <= r) {
            int mid = (l + r) >> 1;
            if (!dsu[mid].same(u, v)) {
                r = mid - 1;
            } else {
                l = mid + 1;
            }
        }

        if (l < K) {
            dsu[l].merge(u, v);
            e[l][u].push_back(v);
            e[l][v].push_back(u);
        }
    }

    vector<int> t(n, -1);
    int ans0 = -1, ans1 = -1;
    for (int i = 0; i < n; ++i) {
        if (t[dsu[K - 1].find(i)] != -1) {
            ans0 = t[dsu[K - 1].find(i)];
            ans1 = i;
            break;
        } else {
            t[dsu[K - 1].find(i)] = i;
        }
    }

    if (ans0 == -1) {
        cout << -1 << '\n';
        return;
    }

    cout << ans0 + 1 << ' ' << ans1 + 1 << '\n';

    vector<int> path;
    bool flag = false;
    auto dfs = [&](auto &&self, int u, int fa, const vector<vector<int>> &e) -> void {
        if (flag) {
            return;
        }
        path.push_back(u);
        if (u == ans1) {
            flag = true;
            cout << path.size() << " ";
            for (int i = 0; i < (int)path.size(); ++i) {
                cout << path[i] + 1 << " \n"[i == (int)path.size() - 1];
            }
            path.pop_back();
            return;
        }
        for (int v : e[u]) {
            if (v == fa) {
                continue;
            }
            self(self, v, u, e);
        }
        path.pop_back();
    };

    for (int i = 0; i < K; ++i) {
        flag = false;
        dfs(dfs, ans0, -1, e[i]);
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int t;
    cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}