经皮给药系统的优点有（）、维持恒定的血药浓度和减少毒副作用、延长作用时间，减少用药次数、患者可自主给药。
参考答案：避免口服给药首过效应和胃肠灭活
—_________ you _________ the terrible news about Libya?
—Yes, I _________ it this morning. The people there will suffer from the war.
A．Do, watch; have done
B．Did, watch; did
C．Have, watched; did
D．Had, watched; will do
—What makes her so _______?
—Her wish to be a singer has come true. [ ]
A. sad
B. angry
C. happy
D. afraid
