Receptive language is the ability to understand/comprehend language, while expressive language is the ability to use/produce language. A mixed receptive-expressive language disorder affects both comprehension and use of language. A child with mixed receptive-expressive language disorder has both receptive and expressive language abilities that are lower than that of other children their age.
Some red flags or warning signs for mixed receptive-expressive language delay/disorder:
Language disorders are evaluated by a Speech-Language Pathologist who uses a variety of assessment tools. The evaluation is conducted to best fit the needs of your child and often includes a combination of standardized measures (to formally compare skills to same-aged peers), informal measures (play, conversation, story retell), and parent- and/or client-interview.
If your child has a mixed receptive-expressive language delay/disorder, treatment will focus on building his/her receptive and expressive communication. Receptive concepts are often targeted first, as it is often easier for a child to demonstrate his/her understanding before developing meaningful and intentional expressive language. Receptive language targets may include pointing to pictures, retrieving or showing objects, following directions, and answering questions. Expressive language tasks may include participation in songs and rhymes, requesting objects or actions, labeling or describing pictures, or answering questions. Therapy sessions will target the specific needs of your child base on their age, interests, and developmental profile. Sessions are often client-led, and may be play-based or planned around more structured activities.
Developmental norms for speech and language (ASHA): https://www.asha.org/slp/schools/prof-consult/norms/
Ages & Stages of Receptive & Expressive Development (birth-5 years): https://www.speech-language-therapy.com