#include <bits/stdc++.h>
using namespace std;

const int N = 100005;

int n, l[N], tmp[5000005][26];
string s[N];
vector<bool> mark[N];

string check(const string &s, const string &t) {
    vector<int> cnt(26, 0);
    for (auto c : s) ++cnt[c - 'a'];
    for (auto c : t) {
        if (--cnt[c - 'a'] < 0) {
            return "0";
        }
    }
    string r;
    for (int i = 0; i < 26; ++i) {
        while (cnt[i]--) {
            r.push_back('a' + i);
        }
    }
    return r;
}

void solve() {
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> s[i];
        l[i] = s[i].size();
        mark[i].assign(l[i], false);
        mark[i][l[i] - 1] = true;
    }

    int L = *max_element(l + 1, l + n + 1);
    for (int i = 0; i <= L; ++i) memset(tmp[i], -1, sizeof tmp[i]);

    for (int i = n - 1; i >= 1; --i) {
        vector<int> cnt(26, 0);
        for (int j = 0; j < l[i + 1]; ++j) {
            ++cnt[s[i + 1][j] - 'a'];
            if (mark[i + 1][j]) {
                int pos = j % l[i];
                for (int c = 0; c < 26; ++c) {
                    if (cnt[c] < 0) {
                        cout << "NO\n";
                        return;
                    }
                    if (~tmp[pos][c] && tmp[pos][c] != cnt[c]) {
                        cout << "NO\n";
                        return;
                    }
                    tmp[pos][c] = cnt[c];
                }
            }
            if ((j + 1) % l[i] == 0) {
                for (auto c : s[i]) {
                    --cnt[c - 'a'];
                }
            }
        }
        fill(cnt.begin(), cnt.end(), 0);
        for (int j = 0; j < l[i]; ++j) {
            ++cnt[s[i][j] - 'a'];
            if (mark[i][j]) {
                for (int c = 0; c < 26; ++c) {
                    if (~tmp[j][c] && tmp[j][c] != cnt[c]) {
                        cout << "NO\n";
                        return;
                    }
                    tmp[j][c] = cnt[c];
                }
            }
        }
        fill(cnt.begin(), cnt.end(), 0);
        s[i].clear();
        for (int j = 0; j < l[i]; ++j) {
            if (~tmp[j][0]) {
                for (int c = 0; c < 26; ++c) {
                    if (cnt[c] > tmp[j][c]) {
                        cout << "NO\n";
                        return;
                    }
                    while (cnt[c] < tmp[j][c]) {
                        ++cnt[c];
                        s[i].push_back('a' + c);
                    }
                }
                mark[i][j] = true;
                memset(tmp[j], -1, sizeof tmp[j]);
            }
        }
    }
    
    cout << "YES\n";
    for (int i = 2; i <= n; ++i) {
        s[i] = "";
        while (s[i].size() < l[i]) s[i] += s[i - 1];
        s[i].resize(l[i]);
    }
    for (int i = 1; i <= n; ++i) cout << s[i] << "\n";
}

int main() {
    memset(tmp, -1, sizeof tmp);
    ios::sync_with_stdio(0), cin.tie(0);

    int T;
    cin >> T;
    while (T--) solve();

    return 0;
}