However, although there have been attempts to define different subtypes, these have not generally resulted in robust categories. The recommendation of the CATALISE panel was that the specific areas of impairment should be assessed and documented for individual children, while recognizing that different children might have different combinations of problems. The areas which can be affected are:

Grammar – This involves the ability to combine words into grammatically correct sentences (syntax) and to combine parts of words together (morphology) such as adding grammatical endings to verbs like -ing or -ed or to add prefixes and suffixes like dis- or -ation. For instance, a child may say me jump here, instead of I jumped here. Comprehension of sentences can also be affected. For instance, there may be difficulty understanding meaning expressed by word order, and so confusion about what is blue in a sentence like the pencil on the shoe is blue, and a tendency to use general knowledge rather than linguistic cues to meaning, or problems in interpreting grammatical markers of number or tense. Semantics – This refers to childrens ability to understand the meaning of words and how meanings are expressed by combining words together. Children with DLD often have limited vocabulary and may make heavy use of a small set of words with rather general meanings. As children with developmental language disorder get older, they may have a hard time understanding that some words have multiple meanings, for example the word "cold", which can mean a low temperature, a sickness, or being unfriendly.
See also
Auditory processing disorder
Dyslexia
Language processing
Linguistics
Origin of speech
Pragmatic language impairment

References
Further reading
Beitchman, J. H., & Brownlie, E. B. (2014). Language Disorders in Children and Adolescents Boston: Hogrefe. ISBN 9780889373389
Paul, Rhea (2007). Language disorders from infancy through adolescence: assessment & intervention. Mosby Elsevier. ISBN 0-323-03685-6. OCLC 487807750. External links
Helpful article by Professor Maggie Snowling: Dyslexia and developmental language disorder: same or different? Talking Point: Check the progress of your childs language development
What Works: Database of evidence-based interventions