As an exchange student，I studied in France for two years.The first time I took a class in the chemistry lab，I was surprised to find that students were fully "armed".Everyone was wearing goggles（护目镜） and gloves.Safety comes first for science lab class.

    My chemistry teacher Mrs.Louise usually gave us the instruction paper the night before the lab class and let us read it.During the class，she first went over the steps and then put us into groups of two to do the experiments （实验）.What was special was that for every lab class，Mrs.Louise changed everyone's lab partner to make them work with different classmates.

    The class was often filled with laughter and screams（尖叫）.We once tried to burn the chemicals and watch the colors of the flames （火焰）.Different chemicals produced different colors of flames，including bright orange and dark green.Many students in my class were surprised."Wow!That's so beautiful!" they screamed.Then they excitedly took pictures，posted them online and sent them to their friends.Mrs.Louise didn't get angry with us at all for our "noises".She herself even too photos with us!

    After finishing an experiment，we had to write a lab report.If we had a big mistake in the experiment，we needed to analyze （分析）why it happened and what we should do to avoid it next time.The lab reports were very important.They made up around 25% of our term grade.

（1）How did the writer feel when he first took the chemistry class in the lab？ 　     　

（2）Why did Mrs.Louise change everyone's lab partner in every lab class？ 　     　

（3）Was Mrs.Louise angry with the students for their "noises"？ 　          　

（4）What did the students have to do after finishing an experiment？ 　         　

（5）What do you think of Mrs.Louise's lab class？