填空题sign→signal

填空题tough

填空题unease

单项选择题A．She is an anthropology professor.B．She has done a lot of research in South America.C．She has had an appointment with Melissa.D．Melissa would give her a call.

单项选择题A．Half of the animals hibernate and half aestivate.B．Most animals in Africa need aestivation.C．Aestivative animals do not all aestivate in trees.D．Those which eat earthworms as their main food must be aestivative animals.