Intonation is a feature of supra-segmental phonology which emcompasses, among others, rhythm, height, pitch range, fundamental frequency and timing, resulting in communicative intelligibility in English. But the feature has not been seriously studied in the second language suituation, and it is the level where language transfer is most noticed among second language users. The study investigated the intonational structure in the speech of Erei-English biliguals, using the speech outputs of the subjects to determine their mastery of tunes (falling and rising), fundamental frequency as well as duration. It is arguably true that the incorrect production of intonational patterns on English would result to ineffective communication, different interpretations and unintelligibility, among many others. Yet, the feature has traditionally been neglected in the second language teaching even when the non-segmental features are studied. The data (four sentences) used for the study were obtained through recorded utterances that were read aloud by the subjects, and were subjected to computerised speech laboratory. Two research objectives and questions were adopted to guide the study. The findings showed that Erei-English bilinguals lack the knowledge of intonation; the falling tune is used in all utterances as compared to the native speaker’s output, thereby do not observe a tone distinction between yes/no question and statement intonationally. They also exhibit a different alternation from the Standard British English (SBE), using more time to produce an utterance. The performance suggests that a majority of Erei-English bilinguals in the study were yet to meet SBE, and that intonation is the final hurdle which many speakers of English as L2 hardly could cross. The study suggested the provision of teaching materials, radio and television language programmes and technology, among others, to help improve communicative intelligibility among Ere-English users in Nigeria.