Give talks on the following three Mini-presentation tasks. For each talk you can prepare for 1-3 minutes and then talk for 1 minute. Record your talks and upload here. You should record and upload the three talks seperately. You can also put down your notes in the answer area. After you submit your answer, you can read the suggested answers. 针对以下三个小演讲任务进行发言。每个发言1分钟,准备时间不超过3分钟,请将你的发言进行录音并提交,请将三个发言分别录音及分别提交。在回答区,你也可以将准备期间的笔记记录下来,但是此项不作要求。提交录音后,你可以在答案处阅读回答建议。 Task 1