Open the lines of communication. Some parents will feel intimidated due to the language barrier unless you provide conference times, translators or other sources of communication for the parents.
Use simple language in communications. While the parents are intelligent adults, their English skills may still be developing. Using big words and longer phrases may be frustrating and embarrassing for parents of an ESL student.
Relay the information you wish to review with the parents one piece at a time. Give the parents will receive ample time to respond to your information. Once they respond and understand, the next piece of information is presented until the whole test is reviewed.