In this scene, Bing Jue is discussing something with other pupils. he is completely engrossed in this discussion. It is also and informal discussion as he is smiling.
In this scene, Wen Kai and Eugene are playing on their laptop. They are completely engrossed in their games and have no attention on their surroundings. this is only an example. they are not playing computer
In this scene, Bing Jue is showing of his branded pink watch which he likes as it matches his relaxed and cool attitude. 
