my english will get better and better.
will 表示会的意思会更加准确
better and better 表示越来越好
better 只表示更好
get 有带有循序渐进的意味
my English is getting better and better.
用现在进行时表示一个持续变化的状态!
My English improves daily!
My command of English is getting better each day!
My English will be better and better.