码
参考答案:在众多属性中能够唯一标识(确定)实体的属性或属性组称为实体的码。
–Did you enjoy ___________ at the party last night, Lingling?
--Yes, I really enjoyed the food and the music there. Thank you.
A.myself
B.himself
C.yourself
D.herself
线极化由线天线产生,圆(椭圆)极化由环状天线产生。