Sign Language (IMAGE) U.S. National Science Foundation Caption Researchers conclude this is because they are not being taught numbers or number words. Here, American sign language for "three," "seven" and "eight" are shown. Credit © 2011 Jupiterimages Corporation Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.