From the little you’ve shown with your question*, you seem to understand the basics of sentence construction, pronoun use* and subject / verb agreement.
*Your follow-up detail was an incomplete sentence, however, which is seldom a good idea, and the pronoun “I” is always capitalized.
Now what you need to do is work on vocabulary. You don’t want to “prolong” your English speaking, I think – unless you really do want to make it “longer”, which is not very sensible. You want to “improve” it. So you need to do it. Use the language; write longer sentences and paragraphs; write complete sentences. Argue with people online (Fluther is great for that!). Use the language.
I’m mindful that you didn’t ask about writing; you asked about speaking. After you’ve written, read what you’ve said out loud. (Even as a native English speaker of nearly 60 years, I still “read in my own voice in my head” what I write, to see how it sounds.) It makes for better writing – and better speaking, too. So to finally improve your English speaking, speak. There’s not only no better way, but there’s other way.