#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define endl '\n'
#define rep(i,l,r) for(ll i=l;i<=r;++i)
#define rep_(i,r,l) for(ll i=r;i>=l;--i)
const ll N = 2e5 + 7;
const ll P = 998244353;
ll qpow(ll x, ll b) {
	ll res = 1;
	while (b) {
		if (b & 1)res = (res * x) % P;
		x = x * x % P;
		b >>= 1ll;
	}
	return res;
}
ll inv(ll x) { return qpow(x, P - 2); }


void solve() {
	ll n; cin >> n;
	string s[8];
	cin >> s[1] >> s[7];
	s[1] = '.' + s[1] + '.', s[7] = '.' + s[7] + '.';
	rep(i, 2, 6) {
		s[i] = "";
		rep(j, 1, n + 2) s[i] += '.';
	}
	int f1 = 0, f2 = 0;
	int p1 = 0, p2 = 0;
	rep(i, 1, n) {
		if (s[1][i] != '#')f1 = 1;
		if (s[1][i] != '.')p1 = 1;
		if (s[7][i] != '#')f2 = 1;
		if (s[7][i] != '.')p2 = 1;
	}
	if (f1 == 0 && f2 == 0) {
		cout << "Yes" << endl;
		rep(i, 1, 7) {
			rep(j, 1, n) {
				cout << "#";
			}
			cout << endl;
		}
	}
	else if (f1 == 1 && f2 == 1) {
		cout << "Yes" << endl;
		rep(i, 1, n) {
			if (p1&&s[1][i] == '.') s[2][i] = '#';
			if (!p1)s[2][1] = '#';
			if (p2&&s[7][i] == '.') s[6][i] = '#';
			if (!p2)s[6][1] = '#';
		}
		ll pos1 = 0, pos2 = 0;
		rep(i, 1, n) {
			if (s[2][i] == '.' && (s[2][i - 1] == '#' || s[2][i + 1] == '#')) {
				s[3][i] = '#';
				pos1 = i;
				break;
			}
		}
		rep(i, 1, n) {
			if (s[6][i] == '.' && (s[6][i - 1] == '#' || s[6][i + 1] == '#')) {
				s[5][i] = '#';
				pos2 = i;
				break;
			}
		}
		if (pos1 == pos2) s[4][pos1] = '#';
		else if (abs(pos1 - pos2) == 1) {
			s[4][pos1] = '#';
		}
		else {
			rep(i, min(pos1, pos2) + 1, max(pos1, pos2) - 1) s[4][i] = '#';
		}
		rep(i, 1, 7) {
			rep(j, 1, n) cout << s[i][j];
			cout << endl;
		}
	}
	else {
		if ((p1 == 0 && f2 == 0) || (p2 == 0 && f1 == 0)) {
			cout << "Yes" << endl;
			rep(i, 1, 7) {
				rep(j, 1, n) cout << s[i][j];
				cout << endl;
			}
			return;
		}
		cout << "No" << endl;
		return;
	}

}
int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int T(1);
	cin >> T;
	while (T--) {
		solve();
	}
}