Category: Class

Present perfect tense is formed by adding the auxiliary verb has/have and the past participle form of the verb.

Affirmative
has + done
have + done

Negative
has not + done
have not + done

Question
Have (subject) done ?
Have (subject) not done ?

USAGE:

1. Present perfect is used when the action continues from the past until now.

Examples:

Their baby has brought them so much joy ever since she was born.
They haven’t woken up since they took a nap earlier this afternoon.
Have you ever ridden a rollercoaster before?

2. Another use of the present perfect tense is when talking about an action that continues up until now.

Examples:

I have met a lot of clients in the past week.
They haven’t seen each other for ages.
Have you heard from Mary yet?

3. Present perfect is used with time expression such as today, this morning, this year etc. when during the time of speaking, these periods are not yet finished.

Amelia has studied very diligently this semester.
I haven’t taken my medicine today.
Have you gone on holiday this year (yet)?

4. Present perfect is also used to say how many times something has happened.

Kim is taking a diving lesson. It’s her first one.
It’s the first time she has dove. (not dives)

Michael has lost his keys again.
This is not the first time this has happened. (not happens)

Frances is calling her clients again.
That’s the fourth time she has called them today. (not called)

Click on this link for a review on Simple Present Tense form.

USAGE:

1. The simple present is used to talk about habits or routines, schedules, and facts.

Examples:

Habit or Routine:

The team trains every single day.
She visits her hometown on holidays.
They like their coffee cold.

Schedules:

He starts work at nine.
Banks open at 8:00 in the morning.
I go to see my dentist twice a year.

Facts or Generalizations:

It rains a lot in my country during spring.
Nurses take care of ailing patients.
The earth revolves around the sun.

2. Another use of the simple present tense is to express about future events, especially  those based on present facts, and when these facts are something fixed like a time-table, schedule, calendar.

Examples:

The delegation arrives at 10:00 tomorrow.
They have Chemistry class every Tuesdays and Thursdays.
The bar opens at 8:00 tonight.
Next Thursday at 2:00, there is a department meeting.
The group rehearsal commences in fifteen minutes.

The marker to is usually a part of an infinitive. However, it is not a vital part or sign of the infinitive. A bare infinitive does not use to.

USES:

1. After the following verbs:

bid, let, make, see, hear, need, dare, help, feel, notice, watch

Correct: He bade his companions enter.
Wrong: He bade his companions to enter.

Correct: Let them stay here.
Wrong: Let them to stay here.

Correct: He made her suffer.
Wrong: He made her to suffer.

Correct: I heard her tell a lie.
Wrong: I heard her to tell a lie.

2. After modal verbs:

will, would, shall, should, may, might, can, could and must

Correct: They will wait.
Wrong: They will to wait.

Correct: She must obey her parents’ rules.
Wrong: She must to obey her parents’ rules.

Correct: Her daughter can speak five languages.
Wrong: Her daughter can to speak five languages.

Correct: You should come to the party tonight.
Wrong: You should to come to the party tonight.

3. After the expressions:

had better, would rather, sooner than and rather than

Correct: They had better do this task.
Wrong: They had better to do this task.

Correct: The rebels would rather die than surrender.
Wrong: The rebels would rather to die than surrender.

Correct: The children would rather play than study.
Wrong: The children would rather to play than study.

4. After some prepositions:

except, but, save and than

Correct: She can do everything but cook.
Wrong: She can do everything but to cook.

Correct: She did nothing except cry.
Wrong: She did nothing except to cry.