Present Continuous Tense

       This tense is used to express an action that is really being done at this time. Sentence in this tense is used more often than the present tense.

Formula Present Continuous Tense
S+Be (am,is,are)+ V ing (Present Participle)

example:
           -          I am sitting on a chair
           -          It is raining now
           -          We are studying English

              Sentence is made negative by adding not after the Verb Be and interrogative sentences in stacking by moving forward Be sentence.
         
           -          I am not eating anyting
           -          It is not raining now

           -          Is it raining now ?
           -          Are you studying English ?