let jane = { firstName: 'Jane', lastName: 'Doe'};
let john = { firstName: 'John', lastName: 'Doe', middleName: 'Smith' }
function sayName({firstName, lastName, middleName = 'N/A'}) {
console.log(`Hello ${firstName} ${middleName} ${lastName}`)
sayName(jane) // -> Hello Jane N/A Doe
sayName(john) // -> Helo John Smith Doe