生物检验包括()和()。
参考答案:生物效价测定;安全性试验
I do not usually celebrate my birthdays until I met him. _______, I do not like any big party because I’m not good at small talk.
A.On the whole
B.On average
C.In addition
D.In other words
利用幅度分离电路可以完成色同步信号与色度信号的分离。