The passive
The active voice shows what something does. The passive voice shows what happens to something. We make the passive with a form of the verb be + past participle.

To Be + Past Participle

1. We do not use the passive with intransitive verbs (verbs that cannot have an object):
   he arrived (not he was arrived)

The passive: use
We use the passive
-when the object is more important than the subject and the agent is either obvious, not important, or unknown:
2. All applications are processed on the spot, (it is obvious that it is the library staff who process the cards)

-in formal writing to make it less personal:
3. You are advised to return the application form within three days, (impersonal)

The active voice is more direct and personal:
I advise you to return the application form within three days.

-when we describe a process:
4. The union is run by seven executive officers who are elected by students.

We do not generally use the passive for natural (or biological) processes, where people are not involved (e.g. the carbon cycle):
5. Plants take up carbon dioxide from the air as part of photosynthesis.

Past perfect simple

We use the past perfect simple
– When we are talking about the past and want to mention something that happened earlier:
1. His father was a composer and his grandfather had also been a musician. (Mozart’s grandfather was a musician and then later his father became a composer)

Sometimes we use words like just or already. Notice that these adverbs go between the auxiliary and the main verb:
2. By the time he was 17, Mozart’s reputation had already begun to spread through Europe.

-We use the simple past tense if the events are mentioned in chronological order:
3. His grandfather was a musician and his father was also a composer.

with words like when, as soon as, by the time, and after to show the order of events:
4. When Mozart was born, five of his siblings had already died. (Mozart’s siblings died first, then Mozart was born)

Notice the difference in meaning between these two sentences:
5. When I got home, my husband cooked dinner. (= I got home and then my husband cooked dinner)

6. When I got home, my husband had cooked dinner. (= my husband cooked dinner before I got home)

-to talk about an indefinite time before a particular point in the past, often with words like always, sometimes, never, before, by + fixed time:
7. His family was richer than they had ever been before. (= they were not as rich at any time before this point in the past)
8. By the time he was six, the little boy had written a composition of his own.

-to report past events using reporting verbs :
9. The man told me he had met my father a long time before.

Present Perfect

We use the present perfect simple to talk about a time period that is not finished (e.g. today, this week):

I’ve written a rough plan this morning. (it is still morning)

to show that something happened at some point in the past before now. We don’t state when it happened:
I’ve collected plenty of information. (at some point before now and I will use it to write my essay).

The following time expressions are often used: ever, never, before, up to now, still, so far.
It’s the longest I’ve ever had to write, (at any point before now)

If we state when something happened we must use the simple past:
I wasted a lot of time last week, (not I have wasted a lot of time last week)

to talk about a present situation that started in the past, usually with for/since:

I’ve worked really hard for the last two weeks. (I’ve worked hard till now)

We use for with a length of time (e.g. for two hours, for three days, for six months) and since with a point in time (e.g. since 2001, since Monday, since ten o’clock, since I was four, since I started the course).
to talk about something that happened at an unstated time in the past but is connected to the present:
I’ve read all the books on the reading list. (I have the notes now)

The following time expressions are often used: recently, just, already, and yet with negatives or questions.
I’ve just got up.
Have you written your assignment yet?

past simple

to talk about single past completed actions. Often the time is mentioned:
A few weeks ago a woman called to report a robbery at her house.

But no time reference is necessary if it is already known:
How did the burglar break in without anybody hearing him? (in the story I just told you about)

to give a series of actions in the order that they happened:
The burglar came in through the front door, picked up the woman’s handbag, emptied it out, and stole her purse.

Present Simple

to talk about regular habits or repeated actions
I get up really early and practice for an hour or so most days.
I use the Internet just about every day.

Words that describe how often or when are often used (e.g. always, generally, normally, usually, often, sometimes, rarely, never, every day, every evening)

to talk about permanent situations:
My parents own a restaurant.

We use the present perfect, not the present simple, to say how long something has continued:
I have worked there since I was 15. (I work there …)

To talk about facts or generally accepted truths:
Students don’t typically have much money.
If you heat water to 100°C, it boils.

The following words are often used: generally, mainly, normally, usually, and traditionally.
to give instructions and directions:
You go down to the traffic lights, then you turn left.
To start the program, first, you click on the icon on the desktop.

To tell stories and talk about films, books, and plays:
In the movie, the tea lady falls in love with the Prime Minister.

1. The production of oil was at its lowest point nearly 10 million barrels at the beginning of 2009.
2. Oil started the year 2009 at 10 million barrels in January.
3. This state produced well above 10 million barrels of oil in Jan 2009.

What do you think makes a business successful?

What do you do for a living?

How do you spell your name? with S or Z?