Linear helpers can be nested in each other and in block helpers. To use one helper inside another, you need to write it in parentheses (**helper**) instead of curly brackets **{{helper}}.**

For example, you can use it in mathematical calculations, when you need to transfer one calculation to another. For example, you can write expression **10 + 5 − 15** like this:

`{{add 10 (subtract 5 15)}}`

You obtain zero.

You can embed as deeply as you need:

`{{add 10 (subtract 5 (multiply (divide 10 2) 3))}}`

And here, you obtain zero again. Mathematically, it can be written as follows: **10 + (5 − ((10** ᛬ **2) × 3))**

In block helpers, for example, we can embed the calculation of client's balance in helper **#gte:**

```
{{#gte (subtract balance cost) 0}}
Great, you have enough money to buy this course
{{else}}
It seems that there is not enough money in your account to buy the course
{{/gte}}
```