### 3.1.3 Nesting music expressions

It is not essential to declare all staves at the beginning; they may be introduced temporarily at any point. This is particularly useful for creating ossia sections – see ossia. Here is a simple example showing how to introduce a new staff temporarily for the duration of three notes:

>     \new Staff {
>       \relative g' {
>         r4 g8 g c4 c8 d |
>         e4 r8
>         <<
>           { f8 c c }
>           \new Staff {
>             f8 f c
>           }
>         >>
>         r4 |
>       }
>     }

Note that the size of the clef is the same as a clef printed following a clef change – slightly smaller than the clef at the beginning of the line. This is usual for clefs printed in the middle of a line.

The ossia section may be placed above the staff as follows:

>     \new Staff = "main" {
>       \relative g' {
>         r4 g8 g c4 c8 d |
>         e4 r8
>         <<
>           { f8 c c }
>           \new Staff \with {
>             alignAboveContext = #"main"
>           } { f8 f c }
>         >>
>         r4 |
>       }
>     }

This example uses `\with`, which will be explained more fully later. It is a means of modifying the default behavior of a single Staff. Here it says that the new staff should be placed above the staff called “main” instead of the default position which is below.

#### See also

Ossia are often written without clef and without time signature and are usually in a smaller font. These require further commands which have not yet been introduced. See Size of objects, and Ossia staves.

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