标准美语发音的13个秘诀 CD 4 Track 10（在线收听）

Chapter 7. Tee Aitch      CD 4 Track 10

I'd like you to consider words as rocks for a moment. When a rock first rolls into the ocean, it is sharp and well defined. After tumbling about for a few millennia, it becomes round and smooth. A word goes through a similar process. When it first rolls into English,it may have a lot of sharp, well-defined vowels or consonants in it, but after rolling off of a few million tongues, it becomes round and smooth. This smoothing process occurs when a tense vowel becomes reduced and when an unvoiced consonant becomes voiced. The most common words are the smoothest, the most reduced, the most often voiced. There are several very common words that are all voiced: this, that, the, those, them, they, their, there, then, than, though. The strong words such as thank, think, or thing, as well as long or unusual words such as thermometer or theologian, stay unvoiced.

The sound of the TH combination seems to exist only in English, Greek, and Castillian Spanish. Just as with most of the other consonants, there are two types—voiced and unvoiced. The voiced THis like a D, but instead of being in back of the teeth, it's 1/4 inch lower and forward, between the teeth. The unvoiced TH is like an S between the teeth. Mostpeople tend to replace the unvoiced TH with S or T and the voiced one with Z or D, so instead of thing, they say sing, or ting, and instead of that, they say zat or dat.

To pronounce TH correctly, think of a snake's tongue. You don't want to take a big relaxed tongue, throw it out of your mouth for a long distance and leave it out there for a long time. Make only a very quick, sharp little movement. Keep your tongue's tip very tense. It darts out between your teeth and snaps back very quickly—thing, that, this. The tongue's position for the unvoiced TH is similar to that of S, but for TH the tongue is extended through the teeth, instead of hissing behind the back of the teeth. The voiced TH is like a D except that the tongue is placed between the teeth, or even pressed behind the teeth. Now we're ready for some practice.