用下列单词的正确形式填空。
（1）Good luck to _____ (you).
（2）Best ______ (wish) to you .
（3）You’re ____ ( I )best friend.
（4）What are you _____ (write) in your letters?
（5） _____ (wish) you happiness every day.
（6）There ____ (be) about forty letters here.
（7）This one ____(be ) for Amy.