___your school like

The report noted that nicotine breathed inby a smoker increased the need of the heart ________ oxygen

Having checked the doors were closed, and ________all the lights were off, the boy opened the door to his bedroom.[ ]

_____ large quantities of things for him to do,but he managed to finish the work as required.

though they are not doubtful at all _______ John will pass the exam, I still wonder ______ he is fully prepared.