CWG1712 constexpr variable template declarations
CWG1715 Access and inherited constructor templates

Singularize to match the surrounding text, and change 'While' to 'When' to
avoid confusion with the 'Whereas' form of 'While'.
CWG1748 Placement new with a null pointer
CWG1750 “Argument” vs “parameter”

Added a missing 'the'.
CWG1751 Non-trivial operations vs non-trivial initialization
CWG1752 Right-recursion in mem-initializer-list
CWG1753 decltype-specifier in nested-name-specifier of destructor