#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")


constexpr int A = 26;
char buf[5'000'010];

int N;
vector<int> L;
Int F[100'010][A];
Int f[100'010][A];

bool solve() {
  const int maxL = *max_element(L.begin(), L.end());
  vector<int> conds(maxL + 1, -1);
  for (int i = N; --i >= 0; ) {
    const int m = L[i];
    if (i + 1 < N) {
      for (int l = m; l <= L[i + 1]; ++l) if (~conds[l]) {
        // condition for s[i][0, l) is f[j]
        const int j = conds[l];
        conds[l] = -1;
        const int q = l / m;
        const int r = l % m;
        for (int a = 0; a < A; ++a) f[j][a] -= q * F[i][a];
        conds[r] = j;
      }
    }
    copy(F[i], F[i] + A, f[i]);
    conds[m] = i;
  }
  
  vector<string> ans(N);
  for (int i = 0; i < N; ++i) {
    ans[i].assign(L[i], '?');
    int cnt[A] = {};
    if (i == 0) {
      int pos = 0;
      for (int l = 1; l <= L[0]; ++l) if (~conds[l]) {
        const int j = conds[l];
        for (int a = 0; a < A; ++a) {
          if (cnt[a] > f[j][a]) return false;
          for (; cnt[a] < f[j][a]; ++cnt[a]) {
            if (pos >= L[0]) return false;
            ans[0][pos++] = 'a' + a;
          }
        }
      }
    } else {
      for (int x = 0; x < L[i]; ++x) {
        ans[i][x] = ans[i - 1][x % L[i - 1]];
        ++cnt[ans[i][x] - 'a'];
      }
    }
    for (int a = 0; a < A; ++a) if (F[i][a] != cnt[a]) return false;
  }
  
  puts("YES");
  for (int i = 0; i < N; ++i) {
    puts(ans[i].c_str());
  }
  return true;
}

int main() {
  for (int numCases; ~scanf("%d", &numCases); ) { for (int caseId = 1; caseId <= numCases; ++caseId) {
    scanf("%d", &N);
    L.resize(N);
    for (int i = 0; i < N; ++i) {
      scanf("%s", buf);
      L[i] = strlen(buf);
      fill(F[i], F[i] + A, 0);
      for (int x = 0; x < L[i]; ++x) {
        ++F[i][buf[x] - 'a'];
      }
    }
    
    const bool status = solve();
    if (!status) {
      puts("NO");
    }
  }
#ifndef LOCAL
  break;
#endif
  }
  return 0;
}