past time: present perfect simple
(a) few and (a) little
(a)round and about
(be) used to + noun or... -ing
(Great) Britain, the United Kingdom, the British Isles and England
-ing form ('gerund')
-ing form after to
-ing form or infinitive?
above and over
across and over
across and through
active verb forms
adjectives ending in -Iy
adjectives without nouns
adverbs of manner
adverbs: position (details)
adverbs: position (general)
after (preposition); afterwards (adverb)
afternoon, evening and night
all (of) with nouns and pronouns
all and every
all and whole
all with verbs
all, everybody and everything
almost and nearly
also, as well and too
although and though
among and between
and after try, wait, go etc
any (= 'it doesn't matter which')
any and no: adverbs
articles: a and an; pronunciation of the
articles: countable and uncountable nouns
articles: special rules and exceptions
articles: talking in general
articles: the difference between a/an and the
as and like
as if and as though
as much/many ... as ...
as well as
as, because and since (reason)
as, when and while (things happening at the same time)
at, in and on (place)
at, in and on (time)
be + infinitive
be with auxiliary do
be: progressive tenses
because and because of
before (preposition) and in front of
begin and start
big, large, great and tall
borrow and lend
both (of) with nouns and pronouns
both with verbs
bring and take
British and American English
broad and wide
but = except
can and could: ability
can and could: forms
can with remember, understand, speak, play, see, hear, feel, taste and smell
can: permission, offers, requests and orders
can: possibility and probability
close and shut
come and go
comparison: comparative and superlative adjectives
comparison: comparative and superlative adverbs
comparison: much, far etc with comparatives
comparison: using comparatives and superlatives
countable and uncountable nouns
do + -ing
do and make
do: auxiliary verb
during and for
during and in
each and every
each other and one another
ellipsis (leaving words out)
emphatic structures with it and what
every and every one
except and except for
excuse me, pardon and sorry
expect, hope, look forward, wait, want and wish
fairly, quite, rather and pretty
far and a long way
farther and further
fewer and less
for + object + infinitive
for, since, from, ago and before
future: present progressive and going to
future: shall and will (interpersonal uses)
future: shall/will (predictions)
future: simple present
gender (masculine and feminine language)
get (+ object) + verb form
get + noun, adjective, adverb particle or preposition
get and go: movement
go ... -ing
go: been and gone
hard and hardly
have (got) to
have (got): possession, relationships etc
have + object + verb form
have: auxiliary verb
hear and listen (to)
here and there
holiday and holidays
how and what... like?
if so and if not
if-sentences with could and might
if: ordinary tenses
if: special tenses
ill and sick
in and into (prepositions)
in spite of
infinitive after who, what, how etc
infinitive of purpose
infinitive without to
infinitive: negative, progressive, perfect, passive
instead of... -ing
inversion: auxiliary verb before subject
inversion: whole verb before subject
it: preparatory object
it: preparatory subject
last and the last
long and for a long time
look (at), watch and see
marry and divorce
may and might: forms
may and might: permission
may and might: probability
modal auxiliary verbs
more (of): determiner
most (of): determiner
much (of), many (of): determiners
much, many, a lot etc
must and have to; mustn't, haven't got to, don't have to, don't need to and needn't
names and titles
neither (of): determiner
neither, nor and not... either
next and nearest
next and the next
no and none
no and not
no and not a/not any
no more, not any more, no longer, not any longer
noun + noun
one and you: indefinite personal pronouns
one: substitute word
other and others
participles used as adjectives
participles: 'present' and 'past' participles (-ing and -ed)
passive structures: introduction
passive verb forms
past tense with present or future meaning
past time: past perfect simple and progressive
past time: past progressive
past time: present perfect progressive
past time: present perfect simple
past time: simple past
past time: the past and perfect tenses (introduction)
perfect tenses with this is the first time..., etc
personal pronouns (I, me, it etc)
play and game
please and thank you
possessive with determiners (a friend of mine, etc)
possessives: my and mine, etc
prepositional verbs and phrasal verbs
prepositions after particular words and expressions
prepositions and adverb particles
prepositions at the end of clauses
prepositions before particular words and expressions
prepositions: expressions without prepositions
present tenses: introduction
present tenses: present progressive
present tenses: simple present
progressive tenses with always
punctuation: quotation marks
punctuation: semi-colons and full stops
questions: basic rules
questions: reply questions
questions: word order in spoken questions
relative pronouns: what
relative pronouns: whose
relatives: identifying and non-identifying clauses
reported speech and direct speech
reported speech: orders, requests, advice etc
reported speech: pronouns; 'here and now' words; tenses
reported speech: questions
road and street
say and tell
should after why and how
should and would
should, ought and must
should: (If I were you) I should ...
since (conjunction of time): tenses
singular and plural: anybody etc
singular and plural: irregular plurals
singular and plural: plural expressions with singular verbs
singular and plural: pronunciation of plural nouns
singular and plural: singular words ending in -s
singular and plural: singular words with plural verbs
singular and plural: spelling of plural nouns
small and little
so am I, so do I etc
so and not with hope, believe etc
some and any
some/any and no article
some: special uses
somebody and anybody, something and anything, etc
spelling and pronunciation
spelling: -ise and -ize
spelling: capital letters
spelling: ch and tch, k and ck
spelling: doubling final consonants
spelling: final -e
spelling: full stops with abbreviations
spelling: ie and ei
spelling: y and i
still, yet and already
subject and object forms
such and so
tall and high
telling the time
tenses in subordinate clauses
this and that
travel, journey and trip
unless and if not
until and by
until and to
used to + infinitive
verbs with object complements
verbs with two objects
weak and strong forms
when and if
whether and if
which, what and who: question words
who ever, what ever, how ever etc
whoever, whatever, whichever, however, whenever and wherever
worth ... -ing
| Affirmative|| Question|| Negative|
| I have worked you have worked, etc|| have I worked? have you worked? etc|| I have not worked you have not worked, etc|
We use the present perfect simple to say that something in the past is connected with the present in some way.
If we say that something has happened, we are thinking about the past and the present at the same time.
We could often change a present perfect sentence into a present sentence with the same meaning.
I've broken my leg. = My leg is broken now. Finished actions: result now
Have you read the Bible? = Do you know the Bible?
We do not use the present perfect simple if we are not thinking about the present.
I saw Lucy yesterday.
(NOT I have seen Lucy yesterday.)
We often use the present perfect to talk about finished actions, when we are thinking of their present consequences: the results that they have now.
Somebody has shot the manager.
The manager is dead.
Have you read the Bible? Mary has had a baby.
I've broken my leg.
Utopia has invaded Fantasia.
Do you know the Bible? Baby.
I can't walk.
We often use the present perfect to give news.
And here are the main points of the news again. The pound has fallen against the dollar. The Prime Minister has said that the government's economic policies are working. The number of unemployed has reached five million. There has been a fire . . . Finished actions: time up to now
We often use the present perfect to ask if something has ever happened; to say that it has happened before-, or that it has never happened; or not since a certain date; or not fora certain period; to ask if it has happened yet; or to say that it has happened already.
Have you ever seen a ghost?
>?EVER^EVER[^~EVER~^ EVERf°°) EVERp] EVER?^>
I've never seen a ghost.
>NEVER^NEVER^ NEVER j^NEVERj^NEVER ^j~^> NOW
I 'm sure we've met before We haven't had a holiday for ages.
I haven't seen Peter since Christmas.
Has Ann come yet? 'Yes, she has already arrived '
Repeated actions up to now
We use the present perfect to say that something has happened several times up to the present.
I've written six letters since lunchtime.
How often have you been in love in your life?
Actions and states continuing up to now
We use the present perfect to talk about actions, states and situations which started in the past and still continue.
We also use the present perfect progressive in this way.
| I've studied hard for years.|| > NOW|
| I've known him since 1960.|| > NOW|
| I've always liked you.|| > NOW|
| How long have you been here?|| > NOW|
| We've always lived here.|| > NOW|
For the difference, see 244.4.
Do not use the simple present to say how long something has gone on.
I've known him since 1960. (NOT I know him . . .)
Present perfect not used
We do not use the present perfect with adverbs of finished time (like yesterday, last week, then, three years ago, in 1960).
I saw Lucy yesterday (NOT I have seen Lucy yesterday.)
Tom was ill last week (NOT -Tom has been ill last week.)
What did you do then? (NOT What have you done then?)
She died three years ago (NOT She has died three years ago.)
He was born in 1960 (NOT -He has been bom in 1960.)
We do not use the present perfect in 'narrative' — when we tell stories, or give details of past events.
For the structure This is the first time I have ....
Precautions while using Mobile Phones
International Sport Events
Benefits of Dandelion
Pink Lakes of the World
Benefits of Passion fruits
Beautiful Christmas Markets
A New Source of Electricity
How Electricity is obtained on a Large Scale
It came to most of us as a surprise that an electric current has magnetic properties and transforms a coil into a veritable magnet. Perhaps it will not surprise us now to learn that a magnet in motion has electric properties and is, in fact, able to produce a current within a wire. This can be proved as follows: -
Attach a closely wound coil to a sensitive galvanometer; naturally there is no deflection of the galvanometer needle, because there is no current in the wire. Now thrust a magnet into the coil. Immediately there is a deflection of the needle, which indicates that a current is flowing through the circuit. If the magnet is allowed to remain at rest within the coil, the needle returns to its zero position, showing that the current has ceased. Now let the magnet be withdrawn from the coil; the needle is deflected as before, but the deflection is in the opposite direction, showing that a current exists, but that it flows in the opposite direction. We learn, therefore, that a current may be induced in a coil by moving a magnet back and forth within the coil, but that a magnet at rest within the coil has no such influence.
An electric current transforms a coil into a magnet. A magnet in motion induces electricity within a coil; that is, causes a current to flow through the coil.
A magnet possesses lines of force, and as the magnet moves toward the coil it carries lines of force with it, and the coil is cut, so to speak, by these lines of force. As the magnet recedes from the coil, it carries lines of force away with it, this time reducing the number of the lines which cut the coil.
FIG. - The motion of a magnet within a coil of wire produces a current of electricity.