之（P） formal

    之,a classical particle, is often used between an attribute and the word it modifies in written Chinese or in a formal dialogue. There are mainly two ways to use 之：

(1）The meaning and usage of 之is similar to those of 的。
                   Attribute +之+N
Examples:
1. 我们洽谈之事已经写进了合同。
The things that we discussed have already been written into the contract.
2. 这件新产品有很多与众不同之处。
The new product is different form others in many ways.

(2) 之can be inserted between subject and a predicate, and change the structure into a noun phrase. 
                   Subj.+之+Predicate=NP
Examples：
3. 现在的生活水平之高，是几十年前无法想象的。
The living standard nowadays is so high that it was hard for people to imagine decades ago.
Substitutive drills: