根据所给词的适当形式填空。（共10小题；每小题1分，满分10分）
小题1: Many birds can live _______________ (comfortable) in Zhalong all year round.
小题2:Did you have a nice time _____  _(ski) last week ?
小题3:—Whose are these bags? —They’re those _______________(hero).
小题4: Suzy ________ (make) a snowman while Kitty was taking some photos.
小题5:_________(wolf) eat smaller animals when they are hungry.
小题6: Do you know the _________(important) of protecting wild animals.
小题7: If the temperature ________ (drop) to 0 C, the water will become ice.
小题8: Thank you for agreeing__________  (let) me go on the trip today.
小题9: Without the guide’s help, the travelers couldn’t find the way back by           (theirs).
小题10: Bad weather sometimes causes ___________ disasters. (nature)