"Language skills" refers to a person's ability to understand, speak, read, and write a language effectively. It means being able to communicate well using words and sentences in a particular language. Full definition
The basic comprehension strategies that children build out of oral language skills in kindergarten and first grade become more complex in second grade and beyond. (ciera.org)
Current evaluation metrics look at the basics of language skills such as spelling, proper grammar, etc. which don't always translate well * pun - intended * in a conversational setting. (elearningindustry.com)
There is also a speaking exercise and some writing exercises to help students develop language skills in a variety of contexts. (tes.com)