#include <bits/stdc++.h>
using namespace std;
using ui = unsigned int;
using ull = unsigned long long;
using ll = long long;
#define endl '\n'
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int maxn = 2e5 + 10;
const int mod = 1000000007;
#define inl inline
#define fr(i, a, b) for (int i = a; i <= b; i++)
#define ford(i, a, b) for (int i = a; i >= b; i--)
#define forall(i, a) for (auto &i : a)

/**
   ____         ___ _____
  / ___| _   _ / _ \___ /
  \___ \| | | | | | ||_ \
   ___) | |_| | |_| |__) |
  |____/ \__, |\___/____/
         |___/
*/
istream &operator>>(istream &in, vector<int> &v)
{
    for (auto &i : v)
        in >> i;
    return in;
}
ostream &operator<<(ostream &out, vector<int> &v)
{
    for (auto &i : v)
        out << i << " ";
    return out;
}
bool _output = 1;

char a[8][maxn];
void solve()
{
    int n;
    cin >> n;
    string s1, s2;
    // cin>>a>>b ;
    cin >> s1 >> s2;
    int f1 = s1.find('.') == string::npos;
    int f2 = s2.find('.') == string::npos;
    // cout << f1 << " " << f2 << endl;
    if (f1 + f2 == 2)
    {
        cout << "Yes" << endl;
        cout << s1 << endl;
        fr(i, 2, 6)
        {
            fr(j, 1, n)
                    cout
                << "#";
            cout << endl;
        }
        cout << s2 << endl;
        return;
    }
    else if (f1 + f2 == 1)
    {
        cout << "No" << endl;
        return;
    }
    fr(i, 1, 7) fr(j, 1, n) a[i][j] = '.';
    fr(i, 1, n) a[1][i] = s1[i - 1];
    fr(i, 1, n) a[7][i] = s2[i - 1];

    fr(i, 1, n)
    {
        if (a[1][i] == '.')
            a[2][i] = '#';
        else
            a[2][i] = '.';
    }

    fr(i, 1, n)
    {
        if (a[7][i] == '.')
            a[6][i] = '#';
        else
            a[6][i] = '.';
    }

    int l1 = -1, l2 = -1;
    fr(i, 1, n) if (a[2][i] == '.')
    {
        if (i > 1 && a[2][i - 1] == '#')
        {
            l1 = i;
            break;
        }
        if (i < n && a[2][i + 1] == '#')
        {
            l1 = i;
            break;
        }
    }

    fr(i, 1, n) if (a[6][i] == '.')
    {
        if (i > 1 && a[6][i - 1] == '#')
        {
            l2 = i;
            break;
        }
        if (i < n && a[6][i + 1] == '#')
        {
            l2 = i;
            break;
        }
    }

    // cout << l1 << " " << l2 << endl;
    a[3][l1] = '#';
    a[5][l2] = '#';
    if (l1 > l2)
        swap(l1, l2);
    if (abs(l1 - l2) <= 1)
    {
        a[4][l1] = '#';
    }
    else
    {
        for (int i = 3; i <= 5; i++)
        {
            fr(j, 1, n)
            {
                if (i == 4 && j > l1 && j < l2)
                {
                    a[i][j] = '#';
                }
            }
        }
    }

    cout << "Yes" << endl;
    fr(i, 1, 7)
    {
        fr(j, 1, n) cout << a[i][j];
        cout << endl;
    }
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int _ = 1;
    if (_output)
        cin >> _;
    while (_--)
        solve();
    return 0;
}