吾該幫幫手. .幫我釋左呢段文牙!

A pysical education teacher blows his whistle to assemble his students in the play ground. Many students are now standing in front of the teacher, one of them is outstandingly tall. Meanwhile, the teacher says";Tallest boy, you come here. How come I have never seen you before? Are you new?". The tallest boy replys"; You do not recognize me, teacher? I am the Weak Boy Keung from last year's class 4A. My mom said I am too weak so she gave me Yakult to drink every single day"; The last scene showing a tiny boy turned into a big strong boy.