#include<iostream>
using namespace std;
int main(){
 int N;
 cin>>N;
 for(int i=0;i<N;i++){
  string S;
  cin>>S;

  if(S=="Y"){
   cout<<"Four"<<endl;
   break;
  }
  if(i==N-1){
   cout<<"Three"<<endl;
  }
 }
 
 return 0;
}