Right form of verb (part -6) use of present continuous, perfect and perfect continuous tense.

1. am/is/are+ (verb+ing) is used with continuous time such as- now, at this moment, today, day by day, gradually etc. 2. have/has + vpp is used with perfect time such as- just, just now, recently, lately, already, not --- yet. 3. have been / has been + ( verb+ing) is used with for/since + time.