The boy()to school already.
A.has taken
B.has been taking
C.is taken
D.has been taken
参考答案:D
天南星具有的功效是
A.燥湿化痰,降逆止呕,消痞散结
B.燥湿化痰,利气散结,消肿止痛
C.燥湿化痰,祛风通络,解毒散结
D.燥湿化痰,祛风解痉,散结消肿
下列光源属于人造光源的是()
A.LD
B.LED
C.LD和LED