用所给词的适当形式填空
①I have two ____ (brother).
②There are two ____ (family) in the picture.
③ The old man has no ____ (son) or ____ (daughter).
④ My ____ (father) sister is my aunt.
⑤In the photo his mother's ____ (parent) are on the left.
已知下列信息:a.
b.
某同学在探究“灯的亮度是否与电压有关”时,将实物按图所示的电路连接,进行实验操作前,作出如下判断,其中合理的是( )