prep1-105,关于to do和of doing的疑惑

EvaCheng

105, Even though it was not illegal for the bank to share it's customers' personal and financial information with an outside marketing company in return for a commission on sales, the state's attorney general accused the bank of engaging in deceptive business practices by failing to honor its promise to its customers to keep records private.
A, by failing to honor its promise to its customers to keep
B, by its failure of honoring its promise to its customers to keep
C, in its failing to honor its promise to its customes of keeping
D, because of its failure in honoring its promise to its customers in keeping
E, because of its failure to honor its promise to its cusomers of keeping

答案是A, 我选了E...看了语法笔记,说因为考点promise to sb to do sth,所以cde可以马上排除,可是我的理解是这样的,of keeping是来修饰名词promise的,银行对记录保密的承诺,这样的理解对吗?
同样是prep的另一道题也是of doing的
69, The proliferation of so-called cybersquatters, people who register the Internet domain names of high-profilt companies in hopes of reselling the rights to those names for a profit, led to passing the Anti-Cybersquatting Consumer Protection Art in 1999, allowing companies to seek up to $100,000 in damages against those who register domain names with the sole intent of selling them later.
A, passing the Anti-Cybersquatting Consumer Protection Art in 1999, allowing companies to seek up to $100,000 in damages against those who register domain names with the sole intent of selling
B, the passage of the Anti-Cybersquatting Consumer Protection Art in 1999, which allows companies to seek up to $100,000 in damages against those who register domain names with the sole intent that they will sell
C, the passage in 1999 of the Anti-Cybersquatting Consumer Protection Art, which allows companies to seek up to $100,000 in damages against those who register domain names with the sole intent of selling
D, the Anti-Cybersquatting Consumer Protection Art, which was passed in 1999, and it allows companies to seek up to $100,000 in damages against those who register domain name with the sole intent to sell
E, the Anti-Cybersquatting Consumber Protection Art, passed in 1999 and allowing companies to seek up to $100,000 in damages against those who register domain names with the sole intent of selling

做这题的时候我选的是intent to do觉得是表示目的,但是答案说是of selling用来修饰intent
究竟什么时候用to do...什么时候用of doing?? 很纠结呀~

EvaCheng

dddddd

lpdeng

好像是intent是动词则加to do; 若是名词则用of