than in commoner than realised

SLDs
are
common - (more)
than - (they are realised)
and
affect - children.
10%
of children


PS - there is no such word as commoner

Re: than in commoner than realised


SLDs = subject of the sentence
are = verb
commoner = predicate adjective
than = subordinate conjunction
realised = elision of we had realised, serving as the second term in the comparison

and = coordinate conjunction linking the predicate affect about 10% of children to the subject SLDs

affect = verb
about = adjective modifying 10%, and introducing the adjectival phrase about 10% of
10% = noun
of = preposition
children = noun, and object of the verb affect

There is such a word as commoner, but it is a noun, and it refers to those who are not of "royal blood."

In this context, one should use "more common." Your question has been answered by others.

Compact Oxford English Dictionary

common

• adjective (commoner, commonest) 1 occurring, found, or done often; not rare.

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Encarta

com·mon [ kómmən ]

adjective (comparative com·mon·er, superlative com·mon·est)

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AHD

common

ADJECTIVE: Inflected forms: com·mon·er, com·mon·est

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