1) because it is cold and its impossible to have a sun bath)
2) because its too hot and sometimes you are dreaming only about the conditioneer)
3)..because after the cold cold winter,finally we can feel the worm sun,we can see some birds and we feel that :the somme is coming up
4) because all around is sad,almost all people have a bad mood,and the weather is rainy and all the time I wamt to sleep)