Ashwini Rao, a Ph. D student, and her team at the Institute of Software Research discovered that using proper grammar in your passwords is a bad idea--one that weakens your security online.
In the article, Stop using proper grammar, its making your passwords weak, Meghan Kelly, a writer at VentureBeat, describes Ashwini Rao's work on how good grammar is much easier to crack when used in a pass code, and the use of pronouns, adverbs and adjectives make it easier for password hackers to decipher.
Rao's studies show that pronouns are significantly easier to crack than nouns simply because there are far fewer of them to draw upon when used in pass phrases. As always with password security, it is best to be random--making it more difficult to crack. Rao will present the full findings at the Association for Computing Machinery’s Conference on February 20th 2013.
SOURCE: VentureBeat: https://venturebeat.com/2013/01/24/password-grammar/