小明和同组同学利用如图所示的a、b两个电路进行“串联电路和并联电路的比较”的探究活动在保持电源电压不变的条件下,他们所记录的实验结果如下.你认为其中不可能的是( )
A:在a电路中,当灯L1和灯L2都发光时,取下灯L1,灯L2将会熄灭
B:在a电路中再串联一个小灯泡,接通电路后,灯L1和灯L2发光会变暗
C:在b电路中,当灯L1和灯L2都发光时,取下灯L1,灯L2将会熄灭
D:在b电路中,当灯L1和灯L2都发光时,取下灯L1,灯L2将会变暗
读课文《怀素写字》内容填空。
怀素____就喜爱____,是个____上进的孩子。怀素写字非常____。他总是____看清____的形状,记住____的笔顺,再一笔一画照着____。
下列关于达尔文的自然选择学说的叙述,不正确的是( )
先通读下面的短文,掌握其大意,然后从A、B、C、D四个选项中选择可以填入空白处的最佳答案。
Today is Sunday.It's1and warm.My parents,my2and I are all at home.My parents don't have to go to3,and my sister and I don't have to go school.We are all in the yard(院子).Look!My father is4his bike.Hd often goes to work by bike.The bike5takes him about ten minutes.My mother is watering the flowers.The flowers make our yard very6.We all like the flowers.My sister is playing with a dog.It's7pet dog.The dog is very smart.My mother often takes the dog out8a walk after dinner.What am I doing?I'm drawing.I like drawing very much.I want to join the9club at school.
It's a nice day and we're10in the yard.How happy we are today!