The answer is definitely D, because it contains two independent clauses that are joined together without a comma or conjunction. (An independent clause just means a chunk of language that has both a subject and a verb and could be a complete sentence on its own.)
Well it depends on what you mean by learning English, though it seems that in this sense you mean learning English as your second language. I do not know what your first language is, so I can not help you as effectively, but in general English is one of the hardest languages to learn with all the grammar rules and words involved. I would get a tutor to help you,use Google Translate, get a language learning program, or a book that teaches you the language. Any one of these works, though some not as effective as others. You build up from the basics and use the language you want to learn as often as you can so you can learn faster
The answer is c sorry if its not right...
I know number 1 is a verb but!