Укажите ошибки в предложениях: 1)Why don39;t you try to wear sunglasses.

Укажите оплошности в предложениях: 1)Why don39;t you try to wear sunglasses. It might help you to avoid having so many headaches. 2)John39;s father has promised to buy him a car, even though he passes his exams. 3)Warning of bad weather in advance the tourists reluctantly returned to their hotel. Если можно, то с разъяснениями.