positive emotion

In class, my professor asked us to list down 'emotion'. We gave her the list - happy, sad, stress, envy, jealous, angry, nervous.... Then professor asked us, in the list , how many was positive emotion ??? the answer was ONE only ( Happy ). Then she told us that reseach showed that the positive vs negative emotion is always 1:3, means among 4 emotion list , 1 is positive, the rest 3 is negative. She reminded us the power of being positive. Usually, most people naturally thinks of negative emotion , or negative things, and we emphasize less on positive emotion or positive behaviours....she reminded us that being a teacher , we need to be more careful, teacher ought to be more observant and praise the children /students when they've done positive behaviours or tasks. Eg when a student has long hair , we may commented negatively on his/her long hair , likewise, when he/she has short hair - did we ever comment the short hair - which could be a better hairstyle ??? sometimes , kids just have to do the negative things to get our attention .... hmm, becareful... start by saying good things about others , OK :)