Chapter 6, page 320, exercise 5 (Edition 9)
(a.) I learned a new word today.
(b.) I learned a new sentence today.
To my knowledge, both these two sentences contain a controversial grammar issue. From the prescriptive grammar aspect, using the present perfect tense, “have learned”, would be more suitable than using past tense, “learned”, when the adverb of time is “today.” Secondly, for native speakers, the (a.) statement is more probable than the (b.) statement. Knowing a language means being able to use the creativity of a language to produce new sentences, even never heard before, by the words that one knows. That is why we can buy a dictionary of words, but we cannot buy a dictionary with all the possible sentences of any language. The reason is that the possibility of sentences can be infinite in any language, and the natives usually have already known all the possibility of sentence structure unconsciously. As a result, the former is a more reasonable one. We will say that a native learn a new word instead of a new sentence. However, the latter could be make sense in the case of non-native speakers who learn the language as a second language.
Chapter 6, page 320, exercise 6 (Edition 9)
Animal “languages”, like the barking of dogs, indeed have something in common with human language. That would be the function of “communicate”. No matter human or animals can receive and send “messages” to their same kind. Although animal “languages” system may be potentially similar to human language, it still remains a far way to human language. It is not because of a lack of speech. We have already known that sounds are not a necessary aspect of language from the evidence of sign language. The differences is that animal “languages” do not exist a creativity ability which is unique in human language. Also, the universal language of human beings do have some discrete units which animal “language” does not. The last, animals cannot associate certain sounds...