"If I don't respond, it doesn't mean I don't understand."
Making the assumption that 'not responding' indicates 'not understanding' can be misleading. If an individual has challenges with expressive language, he may very well understand what you are asking him, or stating to him, or saying in his presence.
"It doesn't help when you say it louder."
Barring any auditory challenges the individual may have, speaking in a louder tone of voice will most likely not illicit a different response from them - and it is usually considered inappropriate.
"I can say, "Thank you" in different ways."
If you know someone with autism who has expressive language challenges, you will learn to pick-up on their more subtle responses. Work on helping him develop more language, but also learn to understand and accept these communications as well.
"I may be able to...if you ask me the right way."
Many skills and activities do not require a verbal response if the learner is directed in the appropriate manner. When working on Math, for instance, asking a student, "Show me which number is larger" or "Write down the larger number" can be more effective than, "Tell me which number is larger." The latter way of asking requires a verbal response from the student, which could be much more difficult than the math problem itself.
While it is important to work on developing a student's receptive and expressive language skills, it is also important to understand, and react appropriately to, the individual's current ability level in this area. There is always a fine line between requiring language from a student (to help them develop the skill) and accepting their approximations. Knowing how to balance these considerations will create a more effective teaching environment and help avoid frustration.
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