EXPRESSIVE LANGUAGE DISORDERS
There are many ways that a child can convey thoughts, feelings, and ideas to others. For some children, communication may be comprised of what is referred to as "pre-verbal" means, such as moving toward or looking at a desired object, pulling a parent along by the hand, gesturing, or showing. When a child begins to use single words, he is showing that he knows that the word can represent his thought or idea. Ideally, children learn to move from single words, to two-word combinations, to basic sentence construction by the time that they are three years old. However, many children experience difficulty in expressive language skills, that may include one or more of the following areas; 

Semantics: This refers to the meaning of language. A child who is struggling in this area may not be able to use vocabulary efficiently to express himself. (i.e. "I ate that fruit, you know the red one with seeds. What do you call that again?") 

Syntax: A child who has difficulty with syntax will show problems with basic sentence construction, and word order. (i.e. "I played after school ball with my friends." Sometimes a child misinterprets language rules, which leads to overgeneralization (as in referring to all people, including females as "he"). 

Morphology: This refers to the basic building blocks of grammar. Examples of "morphological markers" include plurals, the present progressive "ing", and past tense markers. A child who has difficulty using correct morphology may offer a sentence like "The boy run into the house and eated all of the cookie."

Pragmatics: Pragmatics refers to the ability to use language in a way that is socially appropriate with others. While some children struggle in this area because of developmental or neurological disorders (i.e. Autism spectrum), other children show difficulty in pragmatic skills because of generalized weaknesses in receptive and/or expressive language abilities. For example, a child who processes language more slowly in conversation may not have as many  opportunities to share her thoughts or ideas in a group setting. A child who does not understand more complex or figurative language will struggle with humor and sarcasm.  

If you feel that your child may be experiencing difficulty with expressive language, an evaluation by a certified Speech and Language Pathologist will help you to determine if help may be needed. A good evaluation should include a combination of both standardized testing and behavioral assessment, which incorporates developmental probes. Behavioral assessment frequently includes language sample analysis, which should be collected during a relaxed speaking activity with the child.