1 to fly(it is the bst time to do sth.是做某事的最佳时机)
2 snowmen (前面没有定冠词the 和不定冠词a.an修饰,故用复数)
3 third (第三层,要填序数词third,three为基数词)
4 blew (后面有last night故用一般过去时)
5 friendly (形容词：友好的)
6 ourselves(前面是we,此处要填我们自己ourselves)
7 take ( 前面是 you had better,had btter do sth.后要跟动词原形,意为：最好做某事)
8 running (be good at doing sth.擅长做某事)
9 be (前面有助动词do故谓语动词要用动词原形,is 的动词原形是be) (注意：请核对最后这句是be last还是be late 如果是后者,那么意思为：迟到) 希望可以帮到您