Guess what is Jacqueline Wong's deepest memory upon returning to primary school?

Female goddess, Jacqueline Wong (黃心穎) returned to primary school to visit her teacher one week ago and it reminded her many old memories. However, the deepest memory was actually the water fountain and she kneeled down to take photo with it together. On the Internet, Jacqueline uploaded the photo and left a message: "In fact, my height is almost the same when in primary school but why did the