function makeGreeting(language) {
//將會回傳一個函數
return (firstname, lastname){
if (language === 'en') {
console.log('Hello ' + firstname + " " + lastname)
}
if (language === 'es') {
console.log('Hola ' + firstname + " " + lastname)
}
}
}
var greetEnglish = makeGreeting('en');
var greetSpanish = makeGreeting('es');
//invoke
greetEnglish('John', 'Doe');
greetSpanish('John', 'Doe');