An incident in Chemistry lesson

This would be the first time I wrote in English...This is because I hardly use chinese language to express what happened during today's chemistry lessons!

Today,our class had carried out an experiment on redox reaction using titration method...However,this experiment involved lots of calculation...

Our chemistry teacher expected that we will draw the table for the tabulation of data first before entering the class today,but we had already "forgottened" it...This made her felt unwell already...So,she instructed us to do the calculations by ourselves and handed it up to her before 1.35pm...But,we handed up to her at 1.55pm as we hardly could figure out the answers for the questions...She was very angry and did not want to accept our works...She even scolded our class monitor in front of a few teachers...It's just 20 minutes late!!!

I know what she did to us is just want us to fasten our calculations...This is just to teach us a lesson~By the way...Through this experiment report,our relationships improved a lot...(Probably a lot?)haha!!!