The present continuous & perfect tense

The present continuous tense

1. It shows action that is continuing in the present from the past or was to continue from it.
   
   • He is running.
   For example
   
   1.The colleges are reopening in a week.
   (or)The colleges reopen in a week.
   2.Can you tell when our guests are arriving?
   
2. In active voice positive sentences,the first form of the verb takes "ing," and before it "is," "am," "are" are used.
   
   For example
   
   3.I am resting at the moment.
   4.Are the players doing their best?
   
3. In negative sentences,"not" is used between "is," "are," "am," and the main verb.In questions, "is," "are," "am" are placed before the subject.Other question words like "why," "when," "where," "how," etc. are used before "am," "are," "is."
   
   For example
   5.Is she not knitting the sweater?
   6.Are the tourists not going to climb up the mountain.
   7.Are we not (aren't we) practicing the new game well
   8.What gifts are you selecting?(any gifts out of many)
   9.Which of the letters are yours?
   
4. In passive voice sentences, "being" is used after "is," "are," "am," and the third verb form after them.
   
   For example
   
   10.They are being shown the old fort of the city.
   11.Is he (or she) being told about his (or her) true aims?
   
5. In passive voice sentences, "not" is used between "is," "am," "are," and "being."In questions, "is," "am," "are," are used before the subject.Other question words, "where," "when," "how," "why, etc" are used before "is," "am," "are."
   For example
   12.The candidates are not being asked to leave the hall.
   13.Why are we not being examined in this subject?
   14.Why are the politicians not being called to the Assembly?
6. Some verbs,not indicative of action,cannot be used in the continuous form (in any tense).
   
   • see(understand),feel,smell,believe,hope,appear,look,seem,hate,forget,know,like,honor,wish,possess,remain,require,belong to,consist of
     Exception.When any of these verbs indicates physical or mental action,it can be used in the continuous form.

   Correct	This place smells of mint. I have been smelling these flowers.(action)
   Incorrect	This house is consisting of six rooms. (No action)
   Correct	She seems to be very happy today.
   Incorrect	She is seeming to be busy.

The present perfect tense

1. It shows action that has been completely recently or is continuing.
   For example
   1.We have watched the movie.
   2I have played for two hours.(That is, I am still playing or am not playing)
   3.They said to us, "The trouble is over."
2. In negative sentences, "not" is used after "has," "have," and before the main verb.
   For example
   4.I have not tortured anyone in this department.
3. In questions, "has," "have" are used before the subject.The question words, "why," "where, "where," "how," etc. are used before "has," "have."
   For example
   5.Have I cleared the dues?
   6.Have they not (haven't they) qualified for these posts?
   7.Why has she denied your statement?
4. In passive voice, "has been" or "have been" are used after the object.In negative sentences, "not" is used between "has," "have," and "been."In questions, "why," "where," "how," etc. are used before "has," "have."
   For example
   8.We have been told the secret.
   (or)The secret has been told to us.
   9.You have not been asked to attend the class.
   10.Where has he learnt this skill?