#include<iostream>
#include<cstring>
#include<vector>
#include<map>
#include<array>
#include<algorithm>
using namespace std;
using LL = long long;

int match[1005];
bool v[1005];
vector<int> g[1005];

bool find(int x){
    for(auto j : g[x]){
        if (!v[j]){
            v[j] = true;
            if (match[j] == -1 or find(match[j])){
                match[j] = x;
                match[x] = j;
                return true;
            }
        }
    }
    return false;
}

int main(){

#ifdef LOCAL
    freopen("data.in", "r", stdin);
    freopen("data.out", "w", stdout);
#endif

    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);

    int T;
    cin >> T;
    while(T--){
        int n;
        cin >> n;
        map<int, vector<int> > mp1, mp2;
        for(int i = 0; i < n; i++){
            int a, b;
            cin >> a >> b;
            mp1[a].push_back(b);
            mp2[b].push_back(a);
        }
        int m;
        cin >> m;
        map<int, vector<int> > mp3, mp4;
        for(int i = 0; i < m; i++){
            int a, b;
            cin >> a >> b;
            mp3[a].push_back(b);
            mp4[b].push_back(a);
        }
        
        auto norm = [&](map<int, vector<int> > &mp){
            for(auto &[x, v] : mp){
                sort(v.begin(), v.end());
            }
        };

        norm(mp1);
        norm(mp2);
        norm(mp3);
        norm(mp4);

        bool ok = true;

        auto solve = [&](map<int, vector<int> > &mp1, map<int, vector<int> > &mp3, vector<array<int, 3> > &p){
            auto check = [&](int x, int y1, int y2){
                if (!mp3.contains(x)) return false;
                auto &v = mp3[x];
                auto it = upper_bound(v.begin(), v.end(), y1);
                if (it != v.end() and *it < y2) return true;
                return false;
            };

            for(auto &[x, v] : mp1){
                for(int i = 0; i + 1 < v.size(); i++){
                    if (v[i] + 1 == v[i + 1]){
                        ok = false;
                    }
                    if (!check(x, v[i], v[i + 1])){
                        p.push_back({x, v[i], v[i + 1]});
                    }
                }
            }
        };

        vector<array<int, 3> > p1, p2;
        solve(mp1, mp3, p1);
        solve(mp2, mp4, p2);

        if (!ok){
            cout << -1 << '\n';
            continue;
        }

        const int s1 = p1.size(), s2 = p2.size();

        for(int i = 0; i < s1; i++){
            auto [x, y1, y2] = p1[i];
            for(int j = 0; j < s2; j++){
                auto [y, x1, x2] = p2[j];
                if (y > y1 and y < y2 and x > x1 and x < x2){
                    g[i].push_back(j + s1);
                }
            }
        }
        for(int i = 0; i < s1 + s2; i++){
            match[i] = -1;
        }
        for(int i = 0; i < s1; i++){
            for(int j = 0; j < s1 + s2; j++){
                v[j] = false;
            }
            find(i);
        }
        vector<pair<int, int> > ans;
        for(int i = 0; i < s1; i++){
            if (match[i] != -1){
                ans.push_back({p1[i][0], p2[match[i] - s1][0]});
            }
        }
        for(int i = 0; i < s1; i++){
            if (match[i] == -1){
                auto [x, y1, y2] = p1[i];
                ans.push_back({x, y1 + 1});
            }
        }
        for(int i = 0; i < s2; i++){
            if (match[i + s1] == -1){
                auto [y, x1, x2] = p2[i];
                ans.push_back({x1 + 1, y});
            }
        }
        cout << ans.size() << '\n';
        for(auto [x, y] : ans) cout << x << ' ' << y << '\n';
    }

}