The wording in [stmt.block] takes a more explanatory tone, as opposed to the imperative tone used throughout the document.

Perhaps the first sentence could be replaced with:

Compound statements group a sequence of statements into a single statement, sometimes referred to as a block.

although, the use of "statement" three times there sounds a little awkward, so alternatively:

A sequence of statements can be grouped into a single compound statement, sometimes referred to as a block.