#include <bits/stdc++.h>
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define FORR(i,a,b) for (int i=(a);i>=(b);i--)
#define pb push_back
#define pcnt __builtin_popcount
#define show(x) cout<<#x<<" = "<<x<<endl;
#define maxs(x,y) x = max(x,y)
#define mins(x,y) x = min(x,y)
#define fi first
#define se second
#define rng(a) a.begin(),a.end()
#define each(it,c) for(__typeof((c).begin()) it=(c).begin();it!=(c).end();it++)
#define sz(x) (int)(x).size()

using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vpii;
typedef set<int> si;
typedef pair<ll,ll> pll;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pll> vpll;
typedef set<ll> sl;
template<typename T>string join(vector<T>&v)
{stringstream s;FOR(i,0,sz(v))s<<' '<<v[i];return s.str().substr(1);}
ll gcd(ll a,ll b){if(a>b)swap(a,b);for(;a>0;b%=a,swap(a,b));return b;}
int modpow(ll a,ll n,int m){if(a==0)return a;ll p=1;for(;n>0;n/=2,a=a*a%m)if(n&1)p=p*a%m;return (int)p;}

const int iinf = 1e9;
const ll linf = 4e18;
const int mod = 1e9+7;
const double eps = 1e-10;

int n, ans[52];
string s[52], t, s1 = " ", s2 = "  ";
map<string, set<pii> > m;
set<pii> sat[52][2];
main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> n;
  if(n > 52){
    cout << "Impossible\n";
    return 0;
  }
  FOR(i, 0, n){
    cin >> s[i];
    s1[0] = s[i][0];
    s2[0] = s[i][1];
    s2[1] = s[i][2];
    m[s1].insert(pii(i, 0));
    m[s2].insert(pii(i, 0));
    s1[0] = s[i][2];
    s2[0] = s[i][0];
    s2[1] = s[i][1];
    m[s1].insert(pii(i, 1));
    m[s2].insert(pii(i, 1));
    ans[i] = -1;
  }
  each(itr, m){
    each(itr2, itr->second){
      each(itr3, itr->second){
        if(*itr2 == *itr3)continue;
        sat[itr2->fi][itr2->se].insert(pii(itr3->fi, 1-itr3->se));
      }
    }
  }
  FOR(i, 0, n){
    if(ans[i] != -1)continue;
    bool okok = false;
    FOR(j, 0, 2){
      set<pii> st;
      queue<pii> q;
      st.insert(pii(i, j));
      q.push(pii(i, j));
      pii tmp, bad = pii(i, 1 - j);
      bool ok = true;
      while(!q.empty()){
        tmp = q.front();
        if(tmp == bad){
          ok = false;
          break;
        }
        q.pop();
        each(itr, sat[tmp.fi][tmp.se]){
          if(st.find(*itr) == st.end()){
            st.insert(*itr);
            q.push(*itr);
          }
        }
      }
      if(ok){
        okok = true;
        each(itr, st){
          ans[itr->fi] = itr->se;
        }
      }
    }
    if(!okok){
      cout << "Impossible\n";
      return 0;
    }
  }
  FOR(i, 0, n){
    if(ans[i] == 0){
      cout << s[i][0] << " " << s[i][1] << s[i][2] << endl;
    }else{
      cout << s[i][0] << s[i][1] << " " << s[i][2] << endl;
    }
  }
  return 0;
}