By the time the scientists finished working with her she had not fully mastered English grammar and linguists ultimately concluded that because Genie had not learned a first language before the critical period had ended, she was unable to fully acquire a language.
By the time the scientists finished working with Genie, she had not fully mastered English grammar and her rate of acquisition had significantly slowed down. Linguists ultimately concluded that because Genie had not learned a first language before the critical period had ended, she was unable to fully acquire a language.