PRESENT PERFECT TENSE
It is used to describe an action or state that either occurred at an indefinite time in the past (e.g., we have talked before) or began in the past and continued to the present time.
AFFIRMATIVE/POSITIVE
RULE—SUB+HAS/HAVE+V3+OB
- SINGULAR, HE, SHE, IT, NAME—HAS
- I, WE, THEY, YOU, PLURAL—HAVE
FOR EXAMPLE
- He has lived in Australia.
- He has met with an accident.
- We have clicked photographs.
NEGATIVE
RULE—SUB+HAS/HAVE+NOT+V3+OB
FOR EXAMPLE
- He has not taken his medicine.
- They have not completed their project.
- Students have not learned English.
INTERROGATIVE
RULE—HAS/HAVE+SUB+V3+OB?
FOR EXAMPLE
- Have you ever visited Canada?
- Has he cleaned his room?
- Have they taken lunch?
INTERROGATIVE NEGATIVE
RULE—HAS/HAVE+SUB+NOT+V3+OB?
FOR EXAMPLE
- Have you not discussed this with your parents?
- Has he not left his job?
- Have the boys not won the cricket match?