用括号内所给单词的适当形式填空。
1．In big cities, there are many tall _________ (building).
2．I'll probably go _________ (skate) and swimming next year.
3．My cousin was _________ (write) a letter to her mother when I saw her.
4．In English. I'm _________ (good) at reading than listening.
5．My grandparents are over eighty, but they are in good _________ (healthy).