Can't exit of of while loop

[Extreme112]

In the code below I have 3 while loops and I was to use the letter "q" to exit the loop. When testing out the first while loop, I am able to exit the loop fine when pressing typing in "q". However, the other 2 are stuck in an infinite loop and I'm not sure how to exit it.

#include <iostream>
#include <string>
#include <vector>
#include <cctype>

using namespace std;

void make_word_uppercase(string& s){
    for(int i = 0; i < s.size(); ++i){
        s[i] = toupper(s[i]);
    }
}


int main() {

    string word = "";
// This Works
    while(cin >> word){
        if(word == "q"){
            break;
        } else {
            make_word_uppercase(word);
            cout << word;
        }
    }

//  I enter q and it still keeps going
    while(word != "q" && cin >> word){
        make_word_uppercase(word);
        cout << word;
    }

//  Same as above
    while(word != "q"){
        cin >> word;
        make_word_uppercase(word);
        cout << word;
    }
}

[a3625799132]

return 0;

[CodeWriter]

#include <iostream>
#include <string>
#include <vector>
#include <cctype>

using namespace std;

void make_word_uppercase(string& s){
    for(unsigned int i = 0; i < s.size(); ++i){
        s[i] = toupper(s[i]);
    }
}

int main() {

    string word = "";
// This Works
    while(cin >> word){
        if(word == "q"){
            break;
        } else {
            make_word_uppercase(word);
            cout << word;
        }
    }


    while(cin >> word && word != "q"){  //change order of test
        make_word_uppercase(word);
        cout << word;
    }


    while(word != "Q"){
        cin >> word;
        // this changes it to Q and thus will keep going if tested for q
        make_word_uppercase(word);
        cout << word;
    }
    return 0;
}

[Extreme112]

Thanks for the help.