Erros ao usar o console Delégua

[samuelrvg]

PS C:\delegua> escreva(856+4)

Erro:

escreva : The term 'escreva' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included,
verify that the path is correct and try again.
At line:1 char:1

• escreva(856+4)
• CategoryInfo : ObjectNotFound: (escreva:String) [], CommandNotFoundException
• FullyQualifiedErrorId : CommandNotFoundException

[samuelrvg]

Atribuição também esta com erro.

Testar: var x = 1;