✔ 最佳答案
若送氣子音前有S,通常發音時就會不送氣,不過音標是不會變的。
Ex.
STOP /st/,發音時,t會變成d
SKY /sk/,發音時,k會變成g
SPELL /sp/,發音時,p會變成b
所以SQU開頭的字,不管發音為何,音標還是/skw/,但是會發成sgw
可參考維基百科
http://en.wikipedia.org/wiki/English_phonology
當中提到"allophones"的這段
"The voiceless stops /p t k/ are aspirated [pʰ tʰ kʰ] at the beginnings of words (for example tomato) and at the beginnings of word-internal stressed syllables (for example potato). They are unaspirated [p t k] after /s/ (stan, span, scan) and at the ends of syllables."