#include <bits/stdc++.h>
#define rep(i,x,y) for (int i = x; i <= y; i++)
#define repd(i,x,y) for (int i = x; i >= y; i--)
#define mid ((l + r) >> 1)
#define lch (rt << 1)
#define rch (rt << 1 | 1)

using namespace std;

using u32 = unsigned;
using i64 = long long;
using u64 = unsigned long long;

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

    string s, t;
    cin >> s >> t;

    if (s == string(n, '#')) {
        if (t == string(n, '.') || t == string(n, '#')) {
            cout << "Yes\n";
            cout << s << '\n';
            rep(i,2,7) {
                cout << t << '\n';
            }
            return;
        }
        cout << "No\n";
        return;
    }

    swap(s, t);

    if (s == string(n, '#')) {
        if (t == string(n, '.') || t == string(n, '#')) {
            cout << "Yes\n";
            cout << t << '\n';
            rep(i,2,7) {
                cout << s << '\n';
            }
            return;
        }
        cout << "No\n";
        return;
    }

    swap(s, t);

    vector<string> ans(7, string(n, '.'));
    ans[0] = s, ans.back() = t;

    if (s[0] == '.' && s[1] == '.') {
        ans[0][0] = '#';
    }
    if (t[0] == '.' && t[1] == '.') {
        ans.back()[0] = '#';
    }

    rep(i,0,n-1) {
        if (ans[0][i] == '#') {
            ans[1][i] = '.';
        } else {
            ans[1][i] = '#';
        }
        if (ans.back()[i] == '#') {
            ans.end()[-2][i] = '.';
        } else {
            ans.end()[-2][i] = '#';
        }
    }

    int x = find(ans[1].begin(), ans[1].end(), '#') - ans[1].begin();
    rep(j,1,x-1) {
        ans[2][j] = '#';
    }
    if (ans[2] == string(n, '.')) {
        ans[2][0] = '#';
    }
    int y = find(ans[5].begin(), ans[5].end(), '#') - ans[5].begin();
    rep(j,1,y-1) {
        ans[4][j] = '#';
    }
    if (ans[4] == string(n, '.')) {
        ans[4][0] = '#';
    }

    ans[3][0] = '#';

    ans[0] = s;
    ans.back() = t;

    cout << "Yes\n";
    for (auto a : ans) {
        cout << a << '\n';
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int T;
    cin >> T;

    while (T--) {
        solve();
    }

    return 0;
}