A:It's on my birthday.
B:It's my birthday gift.
C:They're birthday gift.
(1)先在试管中加入2mL硫酸铜溶液,然后滴入几滴氢氧化钠溶液,此实验操作需要的仪器除试管外,还需要____ .
(2)如图所示的实验中,将注射器的活塞向右拉时,若装置不漏气可观察到的现象是____
太阳光形成的投影是____ ,手电筒、电灯泡所发出的光线形成的投影是____ .
_________ he is wrong, _________ you should be friendly to him.
- How many___________ do you see?
- Six.( )