1 . 关于金字塔是如何建成的众说纷纭，有人认为是借助运河的水把石料运来的。
There are different opinions on how the pyramids were built. Some people think that the stones ________________.

3 . A c________is a long straight passage dug in the ground and filled with water for boats and ships to travel along; a smaller passage used for carrying water to fields, crops, etc.   (根据首字母单词拼写)