Here you have some answers:
QSQ Have you a doctor on board (or is ... (name of person) on board)? I have a doctor on board (or ... (name of person) is on board).
QSR Shall I repeat the call on the calling frequency? Repeat your call on the calling frequency; did not hear you (or have interference).
QSS What working frequency will you use? I will use the working frequency ... kHz (or MHz) (in the HF bands normally only the last three figures of the frequency need be given).
QSU Shall I send or reply on this frequency (or on ... kHz (or MHz)) (with emissions of class ...)?
Send or reply on this frequency (or on ... kHz (or MHz)) (with emissions of class ...).
if you want more info, please check:http://www.kloth.net/radio/qcodes.php
P.S. Very nice list and Q-code explanation.