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

#define endl '\n'
#define int long long

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

    string a, b;
    cin >> a >> b;

    if (count(a.begin(), a.end(), '#') == n && count(b.begin(), b.end(), '#') != n) {
        cout << "No" << endl;
        return;
    }
    if (count(a.begin(), a.end(), '#') != n && count(b.begin(), b.end(), '#') == n) {
        cout << "No" << endl;
        return;
    }
    if (count(a.begin(), a.end(), '#') == n && count(b.begin(), b.end(), '#') == n) {
        cout << "Yes" << endl;
        for (int i = 1; i <= 7; ++i) {
            cout << a << endl;
        }
        return ;
    }

    vector<vector<char>>v(7, vector<char>(n));
    int p1 = -1, p2 = -1;
    for (int i = 0; i < n; ++i) {
        v[0][i]=a[i];
        if (v[0][i] == '.') {
            v[1][i] = '#';
        }
        else{
            v[1][i]='.';
            if(p1==-1&&((i-1>=0&&a[i-1]=='.')||(i+1<n&&a[i+1]=='.'))){
                p1=i;
            }
        }
        v[6][i]=b[i];
        if (v[6][i] == '.') {
            v[5][i] = '#';
        }
        else{
            v[5][i]='.';
            // cout<<i<<" "<<p2<<endl;
            if(p2==-1&&((i-1>=0&&b[i-1]=='.')||(i+1<n&&b[i+1]=='.'))){
                p2=i;
            }
        }
        // cout<<v[6][i];
    }
    // cout<<endl;
    // cout<<p1<<" "<<p2<<endl;
    if(p2==-1&&p1==-1){
        cout << "Yes" << endl;
        for (int i = 1; i <= 7; ++i) {
            cout << a << endl;
        }
        return ;
    }
    else if(p1==-1){
        cout << "Yes" << endl;
        for (int i = 1; i <= 5; ++i) {
            cout << a << endl;
        }
        for(int i=5;i<=6;++i){
            for(int j=0;j<n;++j){
                cout<<v[i][j];
            }
            cout<<endl;
        }
        return ;
    }
    else if(p2==-1){
        cout << "Yes" << endl;
        for(int i=0;i<=1;++i){
            for(int j=0;j<n;++j){
                cout<<v[i][j];
            }
            cout<<endl;
        }
        for (int i = 1; i <= 5; ++i) {
            cout << b << endl;
        }
        return ;
    }
    else{
        cout<<"Yes"<<endl;
        for(int i=0;i<=n;++i){
            v[2][i]='.';
            v[3][i]='.';
            v[4][i]='.';
        }
        v[2][p1]='#';
        v[4][p2]='#';
        if(p1==p2||p1==p2-1||p1==p2+1){
            v[3][p1]='#';
        }
        else{
            for(int i=min(p1,p2)+1;i<=max(p1,p2)-1;++i){
                v[3][i]='#';
            }
        }
        for(int i=0;i<=6;++i){
            for(int j=0;j<n;++j){
                cout<<v[i][j];
            }
            cout<<endl;
        }
    }
}
signed main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}