Verb conjugation of "disperse" in English

I have contacted you 12 months ago to propose your school's inclusion in our language school directory. I wanted to inform you that our site achieved high positions in search engines last month.
I had never heard the phrase before. In America, there are also different idioms than here in England. It seems that the Americans say it differently than we do here in the United Kingdom.
I really would like to invest more time here but until now I was too busy to keep my promises. Maybe I should take a vacation and go back to Scotland and take another language course there.