「Q」後面一定要加「U」？

No, there are words with Q without U, and it's very populat among Scrabble players to memorize them, becuase sometimes you'll have a Q (high score tile) but no U in your hand to make up words.
FAQIR - Variation of FAKIR, a Hindu ascetic.FAQIRS - Plural of FAQIR.QAID - A variation of CAID, a Muslim leader.QAIDS - Plural of QAID.QANAT - A system of underground tunnels and wells in the Middle East.QANATS - Plural of QANAT.QAT - Variation of KAT, an evergreen shrub.QATS - Plural of QAT.QINDAR - Variation of QINTAR, a monetary unit of Albania.QINDARS - Plural of QINDAR.QINDARKA - Albanian currency.QINDARKAS - The plural of QINDARKA.QINTAR - See above.QINTARS - Plural of QINTAR.QOPH - A letter of the Hebrew alphabet.QOPHS - Plural of QOPH.QWERTY - A standard typewriter keyboard.QWERTYS - The plural of QWERTY, see above.SHEQEL - An ancient unit of weight and money.SHEQALIM - The plural of SHEQEL, see aboveTRANQ - A variation of TRANK (i.e. tranquilizer).TRANQS - Plural of TRANQ.Pronounciation wise, Q without U is still very similar to as if it has a U, another common pronounciation is as if it's a K.

The other reply fm " October " sounds better as he/she has explained the pronounciation matter while the so-called best answer has none.

多數情況下 ,
QU 於字的開頭 , 國際音標是 KW 音 ,
若 Q 後冇 U , 國際音標就沒有 W 音 ,
例外的也有 :
queue 發音為 / kju: /

QU 於字的內部 , 不受此限 , 如 :
cheque 中 , que 只發一個尾音 K
barbeque / ' ba:bikju: / , que 發 kju: 音

2007-03-23 22:35:04 補充：
sorry ,barbecue 先岩