根据句意用括号中单词的适当形式填空,使句子的意思完整、正确。
There are four ___________(season) in a year.
Birds are________ (sing) . They can make beautiful sounds.
It is sometimes ___________ (fog) in autumn and winter.
Birds in Zhalong are in _______(dangerous).
Eddie, you used to share food with______( I ).