UNLESS: usedforsayingthat if somethingdoesnothappen, something else willhappenor betrueas aresultI canthelpyou unless youtellme whatswrong.Thecarshould be in thegarageunless someonesmovedit.

UnlessIn place of if notYoull fail the testunlessyou study.
= Youll fail the testifyoudontstudy.

TYPE 1 CONDITIONAL: UNLESS + PRESENT TENSEWith IfEquivalent with Unless

You will be sick if you don't stop eating.You'll be sick unless you stop eating.

I won't pay if you don't provide the goods immediately.I won't pay unless you provide the goods immediately.

If you don't study dilligently, you'll never understand trigonometry.Unless you study dilligently, you'll never understand trigonometry.

Unless: Substitute for if not.You wont lose any weightunlessyou start /if you don't start eating healthier food.In this situation ,

Did she start eating healthier?

What she should do in order yo lose weight?Is she following her/his advice?

So as a result you should

The first conditional - If and if not:

In conditional sentences, you don't always use 'if' or 'if not'. You can use 'provided that' or 'so long as' instead of 'if'.

For example:
Ifyou put down the gun, I won't call the police. =
So long asyou put down the gun, I won't call the police. =
Provided thatyou put down the gun I won't call the police. =
(Provided thatis more formal thanif.)

You can use 'unless' instead of 'if not'.
For example:
Ifyou don't put the gun down, I'll call the police. =
Unlessyou put the gun down, I'll call the police.

Conditionals: other expressions (unless, should, as long as)fromEnglish Grammar TodayUnlessConditional clauses can begin withunless.Unlessmeans something similar to if not or except if.The verb forms in the examples are similar to sentences withif: we use the present simple in theunless-clause andshall, should, will, would, can, could, mayormightin the main clause:UnlessIphoneyou, youcanassume the trains on time.(If I do not phone you /except if I phone you, you can assume the train is on time.)Well have to cancel the showunlesswesellmore tickets at the last minute.(Well have to cancel the show if we do not sell more tickets/except if we sell more tickets at the last minute.)Warning:We dont useunlessfor impossible conditions:Ifthe government hadnotraised food prices, there would not have been so many protests.Not:Unless the government had raised food pricesWarning:We dont useunlessandiftogether:Well go to the coast tomorrowunlessit rains.Not:Well go to the coast tomorrow unless if it rains.See also:Unless

If so,if not

Should you(Shouldwith inversion)In formal situations, we can useshould+ subject (s) + verb (v) instead ofif:Shouldyouwish to cancel your order, please contact our customer service department on 02317 6658932.(orIf you should wish to cancel your order)Shouldyour childbecome anxious or nervous about any activity, it is a good idea to inform the team-leader.(orIf your child should become)Had you(Hadwith inversion)In formal situations, we can usehad +subject + verb instead ofifin third conditional sentences:HadIknown you were waiting outside, I would have invited you to come in.(If I had known you were waiting outside )HadMargaretrealised she would be travelling alone, she would never have agreed to go.If+were toIn formal situations, we can useif + were towhen we talk about things that might happen but which we think are unlikely:Ifthe Prime Ministerwere toresign, there would have to be a general election within 30 days.In even more formal styles, we usewere+ subject-verb inversion +to-infinitive:[V]Were[S]we[to -INF]to give upthe fight now, it would mean the end of democracy in our country.(If we gave up the fight now )[V]Were[S]the economy[to -INF]to slow downtoo quickly, there would be major problems.(If the economy slowed down too quickly )As long as,so long as,providing, etc.Sometimes we need to impose specific conditions or set limits on a situation. In these cases, conditional clauses can begin with phrases such asas long as, so long as, only if, on condition that, providing (that),provided (that).As long asis more common in speaking;so long asandon condition thatare more formal and more common in writing:[to a group of children]You can play in the living roomas long asyou dont make a mess.So long asa tiger stands still, it is invisible in the jungle.The bank lent the company 100,000 poundson condition thatthey repaid the money within six months.Providing (that) is more common in speaking;provided (that) is more formal and more common in written language:[talking about rail travel in the UK]You can get a senior citizens reductionprovidingyouve got a railcard.They may do whatever they likeprovided thatit is within the law.See also:As long asandso long as

OrandotherwiseWe often useorandotherwisewith conditional meanings:Youve got to start studying,oryoull fail all those exams.(If you dont start studying, you will fail the exams.)[talking about sending a package by mail]Wed better send it express,otherwiseitll take days.(If we do not send it express, it will take days.)SupposingSupposingmay be used with a conditional meaning. It can be used in first, second or third conditional sentences. The speaker invites the listener to imagine a situation:SupposingI dont arrive till after midnight, will the guest-house still be open?(Imagine if I dont arrive till after midnight )Supposingyou lost your passport, youd have to go to the embassy, wouldnt you?Supposinghe hadnt recognised us he might never have spoken to us.See also:In case (of)

Wish

If only

Suppose,supposingandwhat if