双语常用典故： building the house upon the sand 基础不牢固

built on rock 建在磐石上的；基础稳固的出自《新约·马太福音》。

（原文）And every one at heareth these sayings of mine, and doeth them not, shall be likened unto a foolish man, which built his house upon the sand 凡听见我这话不去行的，好比一个无知的人，把房子盖在沙土上。