How to use "You" sentences is an important part of deaf students' written language teaching. Deaf students have more errors of "You" sentences in the Chinese acquisition, which are generally classified into two kinds: "You" should not be used but misused, and "You" should be used but misused. We come to a conclusion that the deaf students' errors of "You" sentences are mainly due to the interference of sign language and also originate from the overgeneralization of the Chinese language and improper learning and teaching strategies. The effective way is to use different teaching strategies according to different errors in order to improve the second language teaching efficiency.