keep the air frsh

keep the air frsh shall i open the window to let some frsh air in no ,i 'd rat keep your hand in the air we should keep the air ___ ___ ___ (清新) 水树奈奈keep your hands in the air中文歌词 help,air,trees,the,keep,clean连词成句句号 Trees Keep the air clean.这句话的意思 Hot air balloons have burners to keep the air hot.动词不定式做定语还是 trees help keep the air clean help后可以直接跟keep吗 The force of air will keep the water in the jar改为一般疑问句 这句话对吗?Greenhouse gases keep heat in the air and make the ear we should open the window to keep the air f______.首字母填空