There are a lot many confusions regarding rules. Different people have different rules, though most of them have many misconceptions. I am going to tell you about rules of forming sentences in each tense. To avoid boredom and tiredness, I will divide this into 3 parts - part 1, part 2 & part 3, each having different tenses.
This is the first part in which I am going to discuss about present tense first of all. I will first tell you the rules, then I will make the words clear to you more even by examples in sample usages.
Present Tense has several forms -
1. Simple Present - This is the most basic Present tense form in which we describe an action which is often and repeatedly done or is just once, but only for the concerned present time.
Affirmative - Subject + 1st form of verb + s/es.
Negative - Subject + do not/does not + 1st form of verb.
Interrogative - Do/does + subject + 1st form of verb ?
2. Present Continuous - In this case, an action which is being done in the present times is being referred.
Affirmative - Subject + is/are/am + 1st form of verb + ing.
Negative - Subject + is/are/am + not + 1st form of verb + ing.
Interrogative - Is/are + subject + 1st form of verb + ing?
3. Present Perfect - It talks about an action which had been started in past but has finished in the present.
Affirmative - Subject + has/have + 3rd form of verb.
Negative - Subject + has/have + not + 2rd form of verb.
Interrogative - Has/have + subject + 3rd form of verb?
3. Present Perfect Continuous - It describes an action which had started in the past but continues in the present.
Affirmative - Subject + has been/have been + 1st form of verb + ing.
Negative - Subject + has not been/have not been + 1st form of verb + ing.
Interrogative - Has/have + subject + been + 1st form of verb + ing.
Now, lets look onto the samples.
1. Simple Present
1. I play chess on my computer.
2. I watch movie once a week.
1. I don't like to travel a lot.
2. I do not want to go to the cinema.
1. Does he like to chat?
2. Does India have a friendly relationship with USA?
2. Present Continuous
1. MLTR is making a new music album.
2. Ravi is having his meal.
1. I am not studying maths.
2. I am not going to school.
1. Is Saurabh watching movie?
2. Is Ram sitting in front of the computer?
3. Present Perfect
1. I have written my notes.
2. I have done my work.
1. Sita has not come to school yet.
2. Ravi has not finished his chores.
1. Have I seen you?
2. Have you visited Taj Mahal?
3. Present Perfect Continuous
1. My uncle has been working for last 30 years.
2. I have been studying in this school since 1999.
1. Shiv has not been attending the class.
2. Aman has not been doing his homework regularly.
1. Has Ram been sitting in front of the computer for hours?
2. Has she been reading this book since last week?