how to set two variables for single IF statement

Hi everyone :) english isn't my first language so please excuse any mistakes

my question is how to set two answers for Choice1 in the following code, if i enter G or Google it redirects to google.com and Y or Yahoo it redirects to yahoo.com

 var CHOICE1 = prompt("Enter Your Choice Google/Yahoo: ");

    if ( CHOICE1 == 'Google' && 'G' ){
        iimPlay('CODE:'+'SET !TIMEOUT_PAGE 100'+'\nURL GOTO=www.google.com');}

    else if ( CHOICE1 == 'Yahoo' && 'Y' ){
        iimPlay('CODE:'+'SET !TIMEOUT_PAGE 100'+'\nURL GOTO=www.yahoo.com');}

I don't have a great knowledge in javascript/programming. I searched Google and tried some of the suggestions but none have worked.

So, whats wrong in this code, and how can I fix it? and thanks in advance