#include<bits/stdc++.h>
#define endl '\n'
#define ll  long long
#define Int __int128
#define pb push_back
#define eb emplace_back
#define MAX_LOG 21
#define ff first
#define ss second
#define M (int)1e4+10
#define ull unsigned long long
#define MAX_LOG 21
//#define double long double
using namespace std;
const double PI=3.1415926535897932385;
const int IIMIN=-2147483648;
//const ll p=998244353;
const ll mod=998244353;
const int INF=0x3f3f3f3f;
typedef pair<ll,ll> PLL;
typedef pair<double,double>PFF;
ll gcd(ll a,ll b)
{
    if(b) while((a%=b)&&(b%=a));
    return a+b;
}//最大公约数函数
ll spid(ll a,ll b,ll p)
{
    ll ans=1;
    while(b)
    {
        if(b&1)ans=ans*a%p;
        b>>=1;
        a=a*a%p;
    }
    return ans;
}//快速幂函数
///小香猪的代码块·香香猪猪惹人怜~
///秋雨想睡觉
const ll N =1e5+10;
char s[10][N];
void solve()
{
    ll n;cin>>n;
    string a,b;cin>>a>>b;
    ll cnt[3]={0};
    for(auto i:a)cnt[1]+=(i=='#');
    for(auto i:b)cnt[2]+=(i=='#');
    if(cnt[1]==n&&cnt[2]==n)
    {
        cout<<"Yes\n";
        for(int i=1;i<=7;i++)cout<<a<<'\n';
        return;
    }else if(cnt[1]==n||cnt[2]==n)
    {
        cout<<"No\n";
        return;
    }
    for(int i=1;i<=7;i++)
    {
        if(i==1)
        {
            for(int j=1;j<=n;j++)
            {
                s[i][j]=a[j-1];
            }
        }else if(i==7)
        {
            for(int j=1;j<=n;j++)
            {
                s[i][j]=b[j-1];
            }
        }else
        {
            for(int j=1;j<=n;j++)
            {
                s[i][j]='.';
            }
        }
        s[i][n+1]='#';
        s[i][0]='#';
    }
    for(int i=1;i<=n;i++)
    {
        if(s[1][i]=='.')s[2][i]='#';
        if(s[7][i]=='.')s[6][i]='#';
    }
//    cout<<'\n';
//    for(int i=1;i<=7;i++)
//    {
//        for(int j=1;j<=n;j++)
//        {
//            cout<<s[i][j];
//        }cout<<'\n';
//    }cout<<'\n';
    PLL up,down;
    for(int i=1;i<=n;i++)
    {
        if(s[2][i]=='#'&&(s[2][i-1]!='#'||s[2][i+1]!='#'))
        {
            if(s[2][i-1]!='#')up={3,i-1};
            else up={3,i+1};
        }
        if(s[6][i]=='#'&&(s[6][i-1]!='#'||s[6][i+1]!='#'))
        {
            if(s[6][i-1]!='#')down={5,i-1};
            else down={5,i+1};
        }
    }
//    cout<<up.ff<<' '<<up.ss<<'\n';
//    cout<<down.ff<<' '<<down.ss<<'\n';
    s[up.ff][up.ss]='#';
    s[down.ff][down.ss]='#';
    if(abs(up.ss-down.ss)<=1)
    {
        s[up.ff+1][up.ss]='#';
    }else
    {
        for(int i=min(up.ss,down.ss)+1;i<=max(up.ss,down.ss)-1;i++)
            s[4][i]='#';
    }
    cout<<"Yes\n";
    for(int i=1;i<=7;i++)
    {
        for(int j=1;j<=n;j++)
        {
            cout<<s[i][j];
        }cout<<'\n';
    }
}
//4
//4
//#..#
//.##.
//5
//##.#.
//.#.##
//6
//######
//.####.
//27
//.######.######.####.#.#####
//.####...####..#.......#####
///秋雨睡觉了
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t=1;
    cin>>t;
    while(t--)
    {
        solve();
    }
}
///记忆是梦的开场白
/*
  */