Write about a time when u were given a big responsibility.

QUESTION : Write about a time when u were given a big responsibility. 
     
           A year ago , my teacher , Mrs Anthony , retired from the teaching profession[职业] . Before she left , my class decided to throw a surprise farewell [离别] party for her . Since i was both a class monitor and a prefect , everyone voted for me to take charge of the planning .
          As i wanted to leave a good impression on Mrs Anthony , i decided to hold the party at the cafe near our school . After liaising[联系] with the cafe owners , i was pleased to know that they would take care of most of the planning including the food and decorations . i left everything in the owners' hands . When my classmates asked if i needed help, i proudly told them that everything was under control. I had underestimated the extent to which i had to get involved with the planning. 
        On the day of the party , everyone made their way to the cafe after school . i had invited another class to join us as well as two other teachers . I opened the door with great finesse once we arrived at the cafe . There were a few gasps and then giggles . One of the other teachers candidly[坦诚的] told me that i was a lousy party planner . Even Mrs Anthony was grinning . 
       I spun around [急转身，猛转回头] to scan the premises[营业场所] . I was shocked to see a bright blue banner strung across[悬挂] the wall that said ' Happy Birthday Mrs Anton '. I was speechless . i apologised profusely to Mrs Anthony and hurried towards the owners , ordering them to take down the banner immediately.By then , everyone had entered the cafe and had seen the banner . My face turned red with embarrassment and annoyance . If only i  had paid more attention to the planning , things would not have turned out this way . 
           The party carried on after the banner was taken down . I still felt discomfited[尴尬] even though no one mentioned the banner . When glasses were raised to toast Mrs Anthony and to wish her luck , someone shouted 'Happy Birthday Mrs Anton ' in jest[玩笑] . Everyone burst out laughing . I bit my lips to prevent myself from retorting[反驳] . The party lasted almost two hours . I was glad when it was over . Although Mrs Anthony patted me on the back and thanked me for the party , i still felt apologetic about the banner . I also knew that i would be the laughing stock[笑柄] of the school once word spread about the banner . 
           The party had certainly thought me to pay attention to detail . I never took things for granted again .