// MagicDark
#include <bits/stdc++.h>
#define debug cerr << "[" << __LINE__ << "] "
#define SZ(x) (int) x.size() - 1
#define all(x) x.begin(), x.end()
#define ms(x, y) memset(x, y, sizeof x)
#define F(i, x, y) for (int i = (x); i <= (y); i++)
#define DF(i, x, y) for (int i = (x); i >= (y); i--)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
template <typename T> inline void chkmax(T &x, T y) {x = max(x, y);}
template <typename T> inline void chkmin(T &x, T y) {x = min(x, y);}
template <typename T> inline void read(T &x) {
	x = 0; int f = 1; char c = getchar();
	for (; !isdigit(c); c = getchar()) if (c == '-') f = -f;
	for (; isdigit(c); c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48);
	x *= f;
}
const int N = 1e5 + 10;
int n;
string st[N];//, ans[N];
typedef array <int, 26> info;
info a[N], O;
void zhk() {
	cin >> n;
	F(i, 1, n) {
		cin >> st[i];
		// st[i] = st[i];
		// ans[i].
		F(j, 0, 25) a[i][j] = count(all(st[i]), char('a' + j));
	}
	vector <pair <int, info>> lim;
	DF(i, n, 2) {
		// info x;
		// F(j, 0, 25) x[j] = count(all(st[i]), char('a' + j));
		vector <pair <int, info>> nlim;
		// info t;
		int w = st[i].size() / st[i - 1].size();
		pair <int, info> t;
		t.first = st[i].size() % st[i - 1].size();
		F(j, 0, 25) {
			if (w * a[i - 1][j] > a[i][j]) {
				cout << "NO\n";
				return;
			}
			t.second[j] = a[i][j] - w * a[i - 1][j];
		}
		for (auto& [a, b]: lim) {
			int x = a / st[i - 1].size();//, y = a % st[i - 1].size();
			a %= st[i - 1].size();
			F(j, 0, 25) {
				if ((b[j] -= ::a[i - 1][j] * x) < 0) {
					cout << "NO\n";
					return;
				}
			}
		}
		lim.push_back(t);
		sort(all(lim));
		lim.resize(unique(all(lim)) - lim.begin());
		F(j, 0, SZ(lim) - 1)
			if (lim[j].first == lim[j + 1].first) {
				cout << "NO\n";
				return;
			}
	}
	// debug << "OK\n";
	int lst = SZ(st[1]);
	info cur = a[1];
	reverse(all(lim));
	lim.emplace_back(0, O);
	for (auto [a, b]: lim) {
		// debug << a << endl;
		F(i, 0, 25)
			if (b[i] > cur[i]) {
				cout << "NO\n";
				return;
			}
		F(i, 0, 25) {
			int t = cur[i] - b[i];
			while (t--) {
				// debug << lst << endl;
				st[1][lst--] = char(i + 'a');
			}
		}
		cur = b;
	}
	// debug << "OK\n";
	F(i, 2, n) {
		int a = st[i].size() / st[i - 1].size(), b = st[i].size() % st[i - 1].size();
		st[i] = "";
		F(j, 1, a) st[i] += st[i - 1];
		F(j, 1, b) st[i] += st[i - 1][j - 1];
	}
	cout << "YES\n";
	F(i, 1, n) cout << st[i] << '\n';
}
signed main() {
	cin.tie(0) -> sync_with_stdio(0); // don't use puts
	int _ = 1;
	cin >> _;
	while (_--) zhk();
	return 0;
}
/* why?
*/