A：实验时，用剩的药品要放回到原试剂瓶中，以免浪费
B：实验时，如果没有说明液体药品的用量时，应取1～2mL
C：给试管里的液体加热时，试管要与桌面成45度角
D：用量筒量取液体时，应使视线与量筒内液体的凹液面的最低处保持水平
This boy is Peter .He is from America．He is ten years old . His hair is yellow.Peter can play basketball. This is his school.It's very big. There are forty students in his class. Miss White is his English teacher. Peter is good at English.
