Что делает цепь for..of и цепь for...in?

Answer 1

for..of => iterate over values
for..in => iterate over properties

but you doesn't deserve my answer, as you let me use googld translate where you have been able to do it yourself ^^

all the more that I previously provided as answer a useful link to a website where you can find all you want to know about es6/js, html, css and more:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in

Answer 2

if you want more chances to get answer, write your question in english ^^

Answer 3

Thanks