#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001

string h = "helloworld";

bool check(string s){
	if(s.size()!=h.size())return false;
	rep(i,s.size()){
		if(s[i]!='?' && s[i]!=h[i])return false;
	}
	return true;
}

int main(){
	int _t;
	cin>>_t;
	rep(_,_t){
		string ans = "-1";
		int n;
		cin>>n;
		string s;
		cin>>s;
		rep(i,s.size()){
			if(check(s.substr(i,h.size()))){
				string t = s;
				rep(j,t.size()){
					if(t[j]=='?')t[j] = 'a';
				}
				for(int j=i;j<i+h.size();j++)t[j] = h[j-i];
				if(ans=="-1")ans = t;
				else ans = min(ans,t);
			}
		}
		cout<<ans<<endl;
	}
	return 0;
}