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

int main() {
  int N;
  cin>>N;
  int z=0;
  for(int i=0;i<N;i++){
    string x;
    cin>>x;
    if(x=="Y"){z++;}
  }
if(z==0){cout<<"Three"<<endl;}
else{cout<<"Four"<<endl;}
}
