People who have lost the ability to speak because of surgery can sometimes use an electronic device that produces sounds imitating the human voice. Known as augmentative communication, these devices include typewriters, speech computers , or special boards with pictures or words. People who are born with a speech impairment and learn ASL at an early age can function well. They may stay within a circle of friends and family who are at ease with them. People who lose the ability to speak due to illness or injury may feel frustrated and impatient when trying to communicate.
Some people can regain their speech or learn to speak well enough to get their meaning across.
It's important to treat a person with a speech impairment normally. People should take their time and be patient when trying to communicate with such a person. Difficulty with speech doesn't have anything to do with intelligence. If understanding is difficult, it may be useful to ask the person to write a word or phrase.