Post Help!: nedd exiplination of Js code

I solve this challenge in edabit.com . When I open the solution of the community I saw a recommended solution I read it but I do not understand a line
Here is the code so far:

function emotify(str) {
	let [first, mid, last] = str.split(" ");
	
	let emotify = {
		"smile": ":D",
		"grin": ":)",
		"sad": ":(",
		"mad": ":P"
	}
	
	return `Make me ${emotify[last]}`;
}

I do not understand the last line of that code:

return `Make me ${emotify[last]}`;

link to that challenge: https://edabit.com/challenge/Szh3ib2bpJCYXKrKa

Here,

is quoted in `` and represents template string in javascript where you can even give expressions with string in ${}.

hence ${emotify[last]} will be replaced with it’s value

Ref:- https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals

Thanks @kashimi
I watched a video on YouTube by freeCodeCamp Channel and it was very helpful
here is the link: https://www.youtube.com/watch?v=kj8HU-_P2NU