用括号中所给单词的适当形式完成下列句子
____ The students took the PISA test in _________ subjects - reading, maths and science. (third)
____ Board games are more and more popular among          . (teenager)
____ I liked to walk in fields on         days and to see my footprints left behind. (snow)
____people often begin their conversations by talking about the weather. (Britain)
____ The news about education has attracted the public attention        (recent)
____ The World Chocolate Park showed a         of many kinds of chocolates. (collect)
____ To improve your writing skills, you'd better         a habit of reading. (development)
____ Don't tell lies. Nobody likes those         people. (honest)

I like these watermelons. _____ sweet.     

热带和温带的分界线是（　　）