let arr1 = [1, 2, 3];  
let arr2 = [...arr1, 4, 5];  
console.log(arr2); // [1, 2, 3, 4, 5]  

let obj1 = {a: 1, b: 2};  
let obj2 = {...obj1, c: 3};  
console.log(obj2); // {a: 1, b: 2, c: 3}