I want to insert formatting text with a single command (I know the text beforehand):

```
 {\addfontfeature{LetterSpace=20.0}Решение}\

```

How do I "bind" it to a macro? I tried:

```
 \def\sol#0 {{\addfontfeature{LetterSpace=20.0}Решение}}
 \let\sol {{\addfontfeature{LetterSpace=20.0}Решение}}

```

Both give errors. I'm sure I'm missing something trivial.