Составить предложения my main reason for studying english is knowing english will help me to i also study english because english will be useful when i

My main reason for studying English is that...it is considered to be the most spoken language all over the world and besides it is relatively easy to learn. 

Knowing English will help me to ...understand people from foreign countries and be able to communicate.

I also study English because ...I like to watch films and read books in the original.