The phrase "wert subsequent to" is spelled using the conventional English spelling system. "Wert" is the past tense form of the verb "to be" and is pronounced /wərt/ (wuhrt). "Subsequent" is spelled with a "b" and pronounced /ˈsʌbsɪkwənt/ (SUV-sik-went). The word "to" is pronounced /tu/ (too) and is commonly spelled as such. The complete phrase means "you were following after." While the spelling may seem unusual, it adheres to established English grammar rules.