【正确答案】Phones can be simply defined as the speech sounds we use when speaking a language．A phone is a phonetic unit or segment．It does not necessarily distinguish meaning；some do，some don’t．For ex ample：[s] and [t] do，as [si:m] and [ti:m] are two words with totally different meaning，and [t] and[t^h] don’t，as [st^hDp]and [stDp] mean the same to a speaker of English．