It is very important to know the tenses in the English language. Most of the ESL learners find ways to learn English without learning the tenses, but it is impossible to do so. Tenses are the first step towards learning English. If you do not know the tenses then your mind is always confused, and whenever you write or speak a sentence in English you are not sure if the words which you utter are right or wrong.
Most of the English is concerned with the 12 tenses of active voice.