9 Statements [stmt.stmt]

9.3 Compound statement or block [stmt.block]

So that several statements can be used where one is expected, the compound statement (also, and equivalently, called “block”) is provided.
compound-statement:
	{ statement-seq }
statement-seq:
	statement
	statement-seq statement
A compound statement defines a block scope ([basic.scope]).
[Note
:
A declaration is a statement ([stmt.dcl]).
end note
]