Impossible past conditions (third conditional)

• if ♦ past perfect would have (done) / (passive would have been done)

Used for the results which would follow from an imaginary post situation. As we cannot change the past, this is an impossible condition. Passive forms are common.

If the ship had had more lifeboats, more passengers would have been saved.

If the ship hadn't hit an iceberg, it wouldn't have sunk.

If another ship hadn't arrived soon afterwards, none of the passengers would have been saved

• Could have and might have are often used Instead of would have, as are other modals.

If the ship had been travelling more slowly. It might have avoided the iceberg.

mixed conditions

• if + past perfect + would (do)

Used for an imagined or actual event in the past with a result in the present.

If she had worn her seal-bell, she would still be alive.

If you hadn't given me a lift. I’d probably still be at the station! ^•

•

0 conditional and /Y-sentences (1)

a You can start doing Section 7. if you ^c Section 1. b If you've become completely contused, you start again,

c Could you get me a book from the library, if l the details,

d If __ a moment, I'll see if l can find another question paper for you. e I’ll go over Ihe figures again, If you

f If you the Instructions, then of course you'll get the answers wrong!

g If you a dictionary, then make sure you know how to use it!

h If 1 finish iny project on lime, I a couple of days off!

a A will finish 0 A will c A give you d A you'll wait r A will think that helps. f A aren’t reading g A will use h A had hotter take

B are going to finish B had better B will give )flll B yvii have wailed B think flint will help. B read B have used B am able to take

C have finished C are going to C have gixru )«//

C yon are waiting C will think that will help. C won't rend C are going to use C am going to take

Complete the sentence with a suitable form of the verb in brackets.

The Earth after humans

If all the people on Earth a {disappear) disappeared tomorrow, nature b (begin) to reclaim the planet, l or a start. If people no

longer c (pollute) the aimosphr-r, lire air d (soon heconie)

elcan again. If there e (he) no people m maintain

buildings, they f (soon begin) to decay, hut more solid

parts g (take) thousands of years to disappear. In general,

if the 6.5 billion humans no longer h (compete) with

other species on Earth, most species «(bcnclit) _ . for

example, if humans no longer j (catch) lish, the numbers

or fish worldwide k (eventually increase) . However, if

humans I (vanish) from the Earth, endangered species of

animals m (not necessarily recover) ..

as some aic already loo few in numbei. Some endangered species n (have) greater difficulty surviving if no humans o (take)

.. ... the trouble to protect them from other species. Even if

wc no longer p (poison) the planet, several decades

q (go by) .. .. before all dangerous chemicals r (disappear)

. And even if the burning of fossil fuels s (ccasc) tomorrow, the oceans t (not absorb)

all the C0₂ in the atmosphere for thousands of years. In the end, though, if alien visitors u (land) on the Earth in 100,000 years lime,

llrey v (find) .. no signs (hat an advanced civilization had

ever lived here.

e conditional and /Y-sentences (1)

a If the Earth (slop) S+opptJ spinning, one side (always be) ,, _ ,

in darkness,

b If ifio polar kv taps finclt) completely, sea-levels worldwide

(rise) by about 60 metres,

e ifwe (recycle) . „ ... more household waste, there (be)

less damage to tire environment.

d If an astronaut (fall) it no a black hole in space, what

(happen) 7

e 1f peopl e (not st op) using cars so m 11 r h, Th r con nt rv's roa (ts

(eventually grind) to a standstill,

f What (happen) when the world's supplies of oil

(run out) ?

g If human beings (finally start) 11vl n g on the Moon, t h ey

(need) to prttdtico watcf art if id a I lye

h If there (not be) any money (the world be)

a better place?

1. Ii we (not stop) ... ovei-fislthig the woi Id's oceans, many species

(become) eMhict.

J If every one In the world (jump) up and down at the same time, there

(he) rtn measurable effect (apart from f>.S billion footprints).

5. Comment on each sentence beginning as shown. Some forms may be passive.

a Mrs Allen's neighbour searched his garden shed, and found the missing cat inside.

If Mrs Alfe-n’s itfcr^UwiC hflJw4 SttanaheJ k/S rj^rdtn SheJ, he аууУкЧ We formd /Hit сд£ inside.

b The hikers who rescued quickly from the storm on the mountain because one ol them had her mobile phone with her.

If . - „ - ... - .

c The 1юу who felt tmo the sea from the boat was wearing a life jacket, so he survived, if

d Mr Anderson woke up because he heard the smoke alarm, and the family managed to escape the fire.

If „ _

e Rescue workers didn't search the car properly and didn't notice the injured man If

f Luckily most oi the staii had left the room to attend a meeting, so only one person was injured by flying glass from Hie broken window.

If -

g United didn't win hccausc the goalkeeper made о mistake in the last minute of the match.

h A police officer stopped Pratt for drink^driving, and took a DN’A sample, which led lo his being charged with lhe previously unsolved murder of Mrs Jones,

©

5. Put the verb in brackets in a suitable form, using a negative where necessary.

The extinction of the dinosaurs

The dinosaurs probably became extinct after a giant asteroid hit the Earth about Ь5 million years ago. But what a (happen) iioa\A Wavf. ИлррлллЛ jf this asteroid b (miss) ? Scientists

believe that in this case, dinosaurs c (continue) to dominate the Earth, and that

modem animals d (probably exist) . Instead of elephants and lions and so on, there

e (be) different types of dinosaur s, because the animals we have now simply

f (be able) .. _ to evolve. Some scientists have even suggested that dinosaurs

у (develop) dluuy the sduie lines ds liuiridii beings, but this Is a iniiiurity view.

The yenerdl view is Ніні perhaps dinosaur brains h (grow) larger, but If they

1. (exist) today, dinosaurs) (change) very much In

general, and k (look) . much the same. I he prospects tor human bemqs would not be

so good, however. It the asteroid I (collide) with the Earth, there m (probably be)

any humans alive today. When the asteroid disaster wiped out the dinosaurs, it

gave mammals the advantage. Without that space collision, mammals n (stand)

much chance against the dominant dinosaur species.

EXTENSION ACTIVITY

A Write some endings for these if-sentences.

a If the weather Rets hotter / colder, b If I was able to live anywhere in the world, c If scientists hadn't discovered how electricity works, d If you waul to learn a foreign language.

B Choose an example from each section on pages 50-51 and translate these examples into your language.

© conditional and /f-sentences (1)

conditional and if-sentences (2)

unless

Unless is used when wo say that if something does not happen, something else will happon (or bo true) as a result.

If you don't help mo, I won't ho able to lift this I won't be able to lift this unless you help me.

otherwise

Otherwise Is another way of saying If not. It can also come at the end of a separate sentence.

Help me with this, otherwise I won’t be able to litt it.

Help me with this. I won't be able to lift it otherwise.

if only

• if only can be used as a way of emphasizing if.

If only you'd told me, I could have helped >ou.

• The If only clause can also be used alone as an exclamation. If only you'd told me!

provided/providing (that), as long as, on condition (that)

These are more emphatic ways of saying only... If.

You can only go to the party, if you arc home before 12.00.

You can qo to the party, provided you are home before 12.00.

You can go to the party, as long as you are home before 12.00.

You can go in the party on condition that you are home hefnrp 12 00

even it

• Even if can also hr used in conditional sentences to emphasize if.

Even if you begged him to take the money, he wouldn't accept.

if (you) should.... it you happen to ...

• If i should emphasizes that an event is not very likely, or to make a request seem more Indirect or polite.

If you should see him tomorrow, could you give him my message?

• it * happen to has a similar effect, and can be used with should to emphasis unlikelihood or distance. Phrases such as by any chance are also used in the same way.

If you happon to bo in the neighbourhood, do drop in and see us.

If you should happen by any chance to find the money, can you send it back?

if (!) were to

• This is nftpn iispH in writing which speculates about the future.

If the government were to lower taxes, they would certainly win votes

• This can also make an event seem less likely.

If I were to offer you more money would you stay in the }ob?

if (it) were /was not for /hadn't been for...

This ripsrrlhps how nnp pvent depends on another

If it were not for Helen, our team would be the worst in the area!

(If Helen wasn't a really good player...)

It it hadn’t been tor Jim. the child would have drowned.

(If Jim hadn’t jumped in to rescue the child ...)

We can use but for to mean 'if it weie not for'.

But for your assistance, we would not have succeeded.

supposing, suppose, imagine

These are ways of expressing conditions without if.

Supposing you had IS million What would you spend it on >

Imagine you were president llow would you change the country >

if so /If not

These can refer to a previous sentence and form a condition.

If lean is too ill to play. Mary can play instead

Jean may be too ill to play, if so, Mary can play instead.

Jean may still be able to play, if not, Mary can play instead.

leaving out If

In everyday speech, we can use an imperative phrase + and + will clause Instead of an //-conditional sentence.

If you come over here. I'll show you what I mean.

Come over here and I'll show you what I mean.

if* adjective

In informal instructions, we can leave out the verb to be in phrases with adjectives such as interested, necessary etc

If you die interested, phone this number If interested, phone this number.

if I might, if I can / could...

Might and can / could are used in an //-clause which stands alone as a very polite request.

If I could just have another look («Could I have another look?)

// / might help you with your coat

had (I)..., were (!)..., should (I)...

It is possible to begir. formal conditional sentences by inverting had or were or should and the subject, leaving out if (see Unit 40).

@ conditional and /f-sentences (2)

a small dogs can be carried on a passenger's knee If only / prtnWfii they do not cause inconvenience to passengers,

b £trrr Iff Supposing you could visit any country in l he world. Where would you go? c I would like to thank the many colleagues who have made Invaluable contributions; unless /but /fjMheir help, this project would not have been possible, d You niusl register your copy of the CD-ROM online, otherwise / unless it wjJI not work, e If L)iv government wen iu 7 \luntil balance the budget, it would lie at lie tel increase spen fling.

You can easily get hue trouble if you happen to be/ tut camtiiion thtii you nrritl the wrong place at the wrong rime.

g We will give you a guaranteed price of €1 SO for your old computer, eum if/otherwise it doesn't work.

h According !o the survey most people in c happy lo ivekome foreigners to their country, us long usfothctwisc they don't sftui behaving like fuidgncis.

■ Please don't interrupt the lesson rts lOfft as flatten you have ait imporwit point to make, j If he slirmM hufipni tu torn*/ If it htulti'i hem fur a leg Injury, Altai i is would pnibahly have wort the race.

2. Choose the correct option, A, B or C, to complete each sentence about security issues.

<; ^c leaving vdludblc piupeily iu pa iked Ldis, then crus wouldn't belnukvii into. b a seilt««trl Pie, lYliat exactly si hjuW yuu do?

c Picase do not u«mhe 999 emergency number you ale reporting a genuine eitterjjency d you were travelling abroad, What could you do to improve your personal safety?

the information provided by members of the public, the police would have a much more dillicull job.

t Police often conduct security checks iu ibis area so they may stop you. and you might be asked for your identity card or passport, g any objectionable items on the website, let us know a nr! we will have them removed,

i CCTV cameras Installed in the store, many shoplifters would escape detection.

1 people locked all Ihelr doors and windows, there would he fewer hreak-lns,

f your computer has a virus protect ion program, you might still fall victim to e mail

scams or malicious softivare.

A A t/uff.ss pimple Slnppi'tl U A Lf'idcss yon witness t A if

cf A Supposing e A Supposing f A otherwise

0. A Unless №11 notice i¹ fh If there were tn he

1. A If truly

j A Unless

B Ittitigine

R if you imr tv u'fftress B provided B If St}

b Provided that nil so

B If jwi happen to notice B If only I here urre R Otliem'fse B £mr If

C If only people stopped CC tf only you witness C unless C /IS Ions as C If it were not for C nicrt if

C If t oil wrtr to notice C Ifil weren't [nr r Fwn If

C On camlitioii llint