[saw] 的音标是 /sɔː/。
其中，['s'] 是一个清音音素，音标为 /s/；['a'] 是一个短元音音素，音标为 /ɔː/；['w'] 是一个辅音音素，音标为 /w/。
这个单词的第一个音素是清音音素 /s/，发音时舌尖靠近上牙齿龈，气流通过口腔中央，发出类似嘶嘶声的音。
第二个音素是短元音音素 /ɔː/，发音时嘴巴要张得比较大，舌头平放在口腔中央，发出口径比较大的音。
第三个音素是辅音音素 /w/，发音时双唇要稍微靠拢，通过唇的摩擦或者闭合释放气流。
总结来说，[saw] 以清音 /s/ 开头，紧接着是短元音 /ɔː/，最后是辅音 /w/。
Using the American Phonetic Alphabet (APA), the pronunciation of [saw] is /sɔː/. The word starts with the voiceless alveolar fricative sound /s/ where the tip of the tongue is near the upper front teeth and air passes through the center of the mouth, creating a hissing sound. The second sound is the short open-mid back rounded vowel /ɔː/, which requires the mouth to be open wide and the tongue placed flat in the center of the mouth, producing a relatively large sound. The final sound is the approximant consonant /w/ where the lips come slightly closer together, allowing for the release or friction of air.
In summary, [saw] is pronounced with the voiceless alveolar fricative /s/ followed by the short open-mid back rounded vowel /ɔː/ and the approximant consonant /w/.