english sound structure part 6. Bài tập luyện ngữ pháp tiếng anh cho mọi người, đây là tài liệu hay và hữu ích có thể giúp các bạn có thể nắm vững được các ngữ pháp tiếng anh cụ thể. | 58 Constituency There is one obvious similarity between the distributions displayed in 28a and 28b . In both series C2 can be occupied by a liquid or glide. The clearest difference between the two distributional patterns is that s can co-occur with a larger set of segments than other Ci consonants. The two main co-occurrence restrictions operating in 28a can be considered characteristic of intra-onset phonotactics. One is a bar on homorganic clusters with 1 and w hence inadmissible tl- dl- 61- pw- bw- . The other is a restriction on C2 being occupied only by a liquid or glide a pattern that is expressible in terms of minimum sonority distance. Note that whenever an obstruent and liquid occur in an order which is the reverse of that in 28a the sonority sequencing principle will debar them from being syllabified within an onset. Thus It for example is an impossible onset on the other hand it con- stitutes a well-formed coda-onset sequence as in . Neither of these restrictions holds of 28b . The homorganic si- sequence is admissible as in sling . And after s C2 can be not only a liquid or glide as in 28a but also a nasal or oral non-continuant. This means that were initial sC clusters to be treated as onsets they would constitute the sole exception to the otherwise general principles of sonority sequencing and minimum sonority distance. Note that sC represents a downward sonority slope in contradistinction to the uniformly upward patterns evident in 28a . And again unlike the pattern in 28a the segments in an s-plus-plosive cluster occupy adjacent positions on the sonority hierarchy. The clusters in 28b are not without their own phonotactic restrictions. However these cannot be considered exclusively diagnostic of onset constituency since they operate in other environments as well. The single factor which has the most far-reaching effect of constricting the contrastive possibilities in C2 in 28b is voicing assimilation between s and a following plosive. This
