ts template literal Cannot find name code example

Example 1: javascript string interpolation

var animal = "cow";
var str=`The ${animal} jumped over the moon`; // string interpolation

Example 2: javascript template literals

//Must use backticks, `, in order to work.

let a = 5;
let b = 10;
console.log(`Fifteen is ${a + b} and
not ${2 * a + b}.`);

//Output:
//Fifteen is 15 and not 20.