#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<cassert>
#include<complex>
#include<numeric>
#include<array>
#include<chrono>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
//ll mod = 1;
//constexpr ll mod = 998244353;
constexpr ll mod = 1000000007;
const int mod17 = 1000000007;
const ll INF = (ll)mod17 * mod17;
typedef pair<int, int>P;

#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;

using ld = double;
typedef pair<ld, ld> LDP;
const ld eps = 1e-10;
const ld pi = acosl(-1.0);

template<typename T>
void chmin(T& a, T b) {
	a = min(a, b);
}
template<typename T>
void chmax(T& a, T b) {
	a = max(a, b);
}
template<typename T>
vector<T> vmerge(vector<T>& a, vector<T>& b) {
	vector<T> res;
	int ida = 0, idb = 0;
	while (ida < a.size() || idb < b.size()) {
		if (idb == b.size()) {
			res.push_back(a[ida]); ida++;
		}
		else if (ida == a.size()) {
			res.push_back(b[idb]); idb++;
		}
		else {
			if (a[ida] < b[idb]) {
				res.push_back(a[ida]); ida++;
			}
			else {
				res.push_back(b[idb]); idb++;
			}
		}
	}
	return res;
}
template<typename T>
void cinarray(vector<T>& v) {
	rep(i, v.size())cin >> v[i];
}
template<typename T>
void coutarray(vector<T>& v) {
	rep(i, v.size()) {
		if (i > 0)cout << " "; cout << v[i];
	}
	cout << "\n";
}
ll mod_pow(ll x, ll n, ll m = mod) {
	if (n < 0) {
		ll res = mod_pow(x, -n, m);
		return mod_pow(res, m - 2, m);
	}
	if (abs(x) >= m)x %= m;
	if (x < 0)x += m;
	//if (x == 0)return 0;
	ll res = 1;
	while (n) {
		if (n & 1)res = res * x % m;
		x = x * x % m; n >>= 1;
	}
	return res;
}
//mod should be <2^31
struct modint {
	int n;
	modint() :n(0) { ; }
	modint(ll m) {
		if (m < 0 || mod <= m) {
			m %= mod; if (m < 0)m += mod;
		}
		n = m;
	}
	operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
bool operator<(modint a, modint b) { return a.n < b.n; }
modint operator+=(modint& a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= (int)mod; return a; }
modint operator-=(modint& a, modint b) { a.n -= b.n; if (a.n < 0)a.n += (int)mod; return a; }
modint operator*=(modint& a, modint b) { a.n = ((ll)a.n * b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, ll n) {
	if (n == 0)return modint(1);
	modint res = (a * a) ^ (n / 2);
	if (n % 2)res = res * a;
	return res;
}

ll inv(ll a, ll p) {
	return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }
modint operator/=(modint& a, modint b) { a = a / b; return a; }
const int max_n = 1 << 20;
modint fact[max_n], factinv[max_n];
void init_f() {
	fact[0] = modint(1);
	for (int i = 0; i < max_n - 1; i++) {
		fact[i + 1] = fact[i] * modint(i + 1);
	}
	factinv[max_n - 1] = modint(1) / fact[max_n - 1];
	for (int i = max_n - 2; i >= 0; i--) {
		factinv[i] = factinv[i + 1] * modint(i + 1);
	}
}
modint comb(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[b] * factinv[a - b];
}
modint combP(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[a - b];
}

ll gcd(ll a, ll b) {
	a = abs(a); b = abs(b);
	if (a < b)swap(a, b);
	while (b) {
		ll r = a % b; a = b; b = r;
	}
	return a;
}
template<typename T>
void addv(vector<T>& v, int loc, T val) {
	if (loc >= v.size())v.resize(loc + 1, 0);
	v[loc] += val;
}
/*const int mn = 2000005;
bool isp[mn];
vector<int> ps;
void init() {
	fill(isp + 2, isp + mn, true);
	for (int i = 2; i < mn; i++) {
		if (!isp[i])continue;
		ps.push_back(i);
		for (int j = 2 * i; j < mn; j += i) {
			isp[j] = false;
		}
	}
}*/

//[,val)
template<typename T>
auto prev_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	if (res == st.begin())return st.end();
	res--; return res;
}

//[val,)
template<typename T>
auto next_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	return res;
}
using mP = pair<modint, modint>;
mP operator+(mP a, mP b) {
	return { a.first + b.first,a.second + b.second };
}
mP operator+=(mP& a, mP b) {
	a = a + b; return a;
}
mP operator-(mP a, mP b) {
	return { a.first - b.first,a.second - b.second };
}
mP operator-=(mP& a, mP b) {
	a = a - b; return a;
}
LP operator+(LP a, LP b) {
	return { a.first + b.first,a.second + b.second };
}
LP operator+=(LP& a, LP b) {
	a = a + b; return a;
}
LP operator-(LP a, LP b) {
	return { a.first - b.first,a.second - b.second };
}
LP operator-=(LP& a, LP b) {
	a = a - b; return a;
}

mt19937 mt(time(0));

const string drul = "DRUL";
string senw = "SENW";
//DRUL,or SENW
//int dx[4] = { 1,0,-1,0 };
//int dy[4] = { 0,1,0,-1 };

//------------------------------------


const int sz = 240;
using bt = bitset<sz>;
int dx[4] = { 1,0,-1,0 };
int dy[4] = { 0,1,0,-1 };
bt adj[sz];

void expr() {
	int n = 5; cin >> n;
	auto isin = [&](int i, int j) {
		return 0 <= i && i < n && 0 <= j && j < n;
	};
	rep(i, n)rep(j, n) {
		for (int dx = -1; dx <= 1; dx++) {
			for (int dy = -1; dy <= 1; dy++) {
				int ni = i + dx;
				int nj = j + dy;
				if (isin(ni, nj)) {
					adj[i * n + j][ni * n + nj] = 1;
				}
			}
		}
	}
	//cout << adj[0][1] << "\n";
	vector<string> s(n);
	rep(i, n) {
		s[i].resize(n, '.');
	}
	int cnt = 0;
	int obj = (n - 2) * 2; obj = 28;
	unordered_map<bt,int> mp[sz];
	function<void(int, bt)> dfs = [&](int id, bt b) {
		if (mp[id].find(b) != mp[id].end()) {
			if (mp[id][b] >= cnt)return;
		}
		mp[id][b] = cnt;
		//rep(i, n)cout << s[i] << "\n";
		//cout <<id<<" "<< b[id] << "\n";
		if (id == n * n) {
			if (cnt > obj) {
				cout << "bad\n"; exit(0);
			}
			assert(cnt <= obj);
			if (cnt == obj) {
				cout << "found\n";
				rep(i, n)cout << s[i] << "\n";
				//exit(0);
			}
			return;
		}
		int rest = n * n - b.count();
		//rest = (rest + 1) / 3;
		rest /= 2;
		if (cnt + rest < obj)return;
		//add
		if (!b[id]) {
			int x = id / n;
			int y = id % n;
			if (x + 1 < n && !b[id + n]) {
				bt nb = b;
				nb |= adj[id];
				nb |= adj[id + n];
				s[x][y] = '#';
				s[x + 1][y] = '#';
				cnt++;
				dfs(id + 1, nb);
				cnt--;
				s[x][y] = '.';
				s[x + 1][y] = '.';
			}
			if (y + 1 < n && !b[id + 1]) {
				bt nb = b;
				nb |= adj[id];
				nb |= adj[id + 1];
				s[x][y] = '#';
				s[x][y + 1] = '#';
				cnt++;
				dfs(id + 1, nb);
				cnt--;
				s[x][y] = '.';
				s[x][y + 1] = '.';
			}
			

		}
		//through
		bt nb = b;
		nb[id] = 1;
		dfs(id + 1, nb);
	};
	bt ori = 0;
	dfs(0, ori);
	cout << "not found\n";
}
void solve() {
	int n; cin >> n;
	vector<string> s(n);
	rep(i, n) {
		s[i].resize(n, '.');
	}
	for (int j = 0; j < n; j += 2) {
		for (int i = 0; i + 1 < n; i += 3) {
			s[i][j] = s[i + 1][j] = '#';
		}
	}
	if (n % 6 == 5) {
		//
	}
	else if (n % 6 == 4) {
		for (int i = 0; i + 1 < n; i += 3) {
			int j = n - 2;
			s[i][j] = s[i + 1][j] = '.';
		}
		for (int i = 0; i < n; i += 2) {
			int j = n - 2;
			s[i][j] = s[i][j + 1] = '#';
		}
		for (int j = 0; j + 1 < n; j += 3) {
			s[n - 1][j] = s[n - 1][j + 1] = '#';
		}
		s[n - 2][n - 2] = '.';
		s[n - 1][n - 1] = '#';
	}
	else if (n % 6 == 3) {
		for (int j = 0; j < n; j += 2) {
			int i = n - 3;
			s[i][j] = s[i + 1][j] = '.';
		}
		for (int i = n - 3; i < n; i += 2) {
			for (int j = 0; j + 1 < n; j += 3) {
				s[i][j] = s[i][j + 1] = '#';
			}
		}
	}
	else if (n % 6 == 2) {
		for (int i = 0; i + 1 < n; i += 3) {
			int j = n - 2;
			s[i][j] = s[i + 1][j] = '.';
		}
		for (int i = 0; i < n; i += 2) {
			int j = n - 2;
			s[i][j] = s[i][j + 1] = '#';
		}
	}
	else if (n % 6 == 1) {
		for (int j = 0; j + 1 < n; j += 3) {
			s[n - 1][j] = s[n - 1][j + 1] = '#';
		}
	}
	else {
		assert(n % 6 == 0);
		for (int j = 0; j < n; j += 2) {
			int i = n - 3;
			s[i][j] = s[i + 1][j] = '.';
		}
		for (int i = n - 3; i < n; i += 2) {
			for (int j = 0; j + 1 < n; j += 3) {
				s[i][j] = s[i][j + 1] = '#';
			}
		}
		for (int i = 0; i + 1 < n; i += 3) {
			int j = n - 2;
			s[i][j] = s[i + 1][j] = '.';
		}
		for (int i = 0; i < n; i += 2) {
			int j = n - 2;
			s[i][j] = s[i][j + 1] = '#';
		}
		vector<string> adj = {
			"...",
			"#.#",
			"#.#"
		};
		rep(x, 3)rep(y, 3) {
			s[n - 3 + x][n - 3 + y] = adj[x][y];
		}
	}
	/*for (int j = 0; j < n; j += 2) {
		if (j + 1 == n - 1) {
			for (int i = 0; i < n; i += 2) {
				s[i][j] = s[i][j + 1] = '#';
			}
		}
		else {
			for (int i = 0; i + 1 < n; i += 3) {
				s[i][j] = '#';
				s[i + 1][j] = '#';
			}
		}
	}
	if (n % 3 == 1&&n>1) {
		for (int j = 0; j+1 < n; j += 3) {
			s[n - 1][j] = '#';
			s[n - 1][j + 1] = '#';
		}
		if (n % 2 == 0) {
			s[n - 2][n - 2] = '.';
			s[n - 1][n - 1] = '#';
		}
	}
	if (n % 3 == 0) {

	}*/
	int c = 0;
	rep(i, n)rep(j, n)if (s[i][j] == '#')c++;
	int obj = n * n / 4;
	c /= 2;
	rep(i, n)cout << s[i] << "\n";
	//cout << c << " " << obj << "\n";
}




signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed<<setprecision(10);
	//init_f();
	//init();
	//while(true)
	//expr();
	int t; cin >> t; rep(i, t)
	solve();
	return 0;
}