Animals cannot survive for long without water. • So desert animals have to find different ways of coping.The first sentence says what cannot happen or be done; the second tells us what must, therefore, be done, what it is necessary to do. Complete these sentences using cannot and have to/has to.1. You ______ reach the island by land or air; you ______ go by boat.2. We ______ see bacteria with our eyes; we ______ look at them through a microscope.3. He ______ have a new bicycle now; he ______ wait till next year.4. Old people often ______ hear very well; they ______ use a hearing aid.5. Road users ______ do what they wish; they ______ follow the traffic rules.6. She ______ accept this decision; she ______ question it.7. You ______ believe everything you hear; you ______ use your own judgement.