1 . Especially amazing is the Inca’s dry stone method of building. Inca builders cut stones to _______________________so that nothing was needed to hold walls together _______________________of the stone. (根据句意填空)

2 . ______ will take you on amazing paths through the Andes Mountains the city of Machu Picchu. After reaching your destination, you will have a day to explore and ______. Especially amazing is the Incas’ dry stone method of building. Inca builders cut stones to exact sizes so that nothing was needed to hold walls together ______ of the stones. (根据课文填空)

3 . Inca builders cut stones to exact sizes so that nothing was needed to ________ walls together,_______ the perfect fit of the stones. (根据课文内容填空)