I learn English experience

I have studied  english for many years in school,but i can't write , understand and speak it , i can just read some simple sentences ,when i started work i realized english was very important,so i joined the english train(?),and i saw my english was improving but very slowly ,so i gave up on learning english for three years. Now i need communication  in english for my work ,so i need to start learning english again . This time i will learn english better and i will try harder by  keep reading and writting every day, i hope other people help me to improve my english.