Conditionals for IELTS Writing and Speaking: types, uses and errors

A conditional sentence says that one thing depends on another. “If prices fall, demand will rise” is an argument in six words, and a structure with several ways to go wrong. This guide explains the types, what each does in a Writing Task 2 argument and a Speaking Part 3 answer, and the errors that cost marks. For how IELTS treats grammar as a whole, start with the pillar guide to IELTS grammar.

What the criterion asks of a conditional

IELTS.org weights Grammatical Range and Accuracy equally with the other three criteria in both Writing and Speaking. The public descriptors, in this site’s Writing band descriptors explorer and Speaking explorer, describe a range of complex sentences used with control, and errors that are less frequent as the bands rise. They do not name conditionals, and IELTS publishes no list of structures to use.

A conditional is range, because it joins two clauses in a particular way, but range only counts alongside accuracy. A third conditional with the wrong verb forms shows you tried and failed, which is not what the descriptors reward. The post on common grammar mistakes in Speaking makes the same point about mixing forms; this guide shows how to choose each type.

The four main types

Every conditional has two halves: the if-clause (the condition) and the main clause (the result). The order can be reversed. When the if-clause comes first, put a comma after it. Invented examples throughout.

Zero conditional

“If water reaches 100 degrees Celsius, it boils.” Use it for facts, rules and habits. “If” here means “whenever”. In Task 2 it states a general principle you then build on: “If a city has no cycle lanes, few people cycle.”

First conditional

“If the council raises parking charges, fewer people will drive into the centre.” Use it for a real possibility and its likely result. It is the natural way to state a consequence in an argument or a recommendation. The if-clause is in the present simple, even though it refers to the future.

Second conditional

“If cities banned private cars, air quality would improve.” Use it for something unlikely, imagined or contrary to the present. The verb in the if-clause is past in form but present in meaning, which is why many learners misread it. It is the main tool for speculating in Speaking Part 3 and for a hypothesis in Task 2.

With “be”, the if-clause often uses “were” for all persons in careful writing: “If I were the minister, I would fund more libraries.” “Was” is also heard in speech.

Third conditional

“If the planners had listened to residents, the road would have been built elsewhere.” Use it for a past situation that did not happen and its imagined result. In an exam answer it suits a lesson from the past or a regret, such as one about the choices someone made when studying. It needs two exact forms, “had” plus past participle, then “would have” plus past participle, and each is a place to slip.

Mixed conditionals

A mixed conditional links a past condition to a present result, or the reverse. The most useful form combines a third-conditional if-clause with a second-conditional result:

• “If I had studied engineering, I would be working abroad now.” The condition is in the past, and the result is in the present.

The other direction links a present state to a past result:

• “If she were more organised, she would have finished the report yesterday.”

IELTS does not require mixed conditionals. They can be natural in a Speaking answer about your own life, but use one only if you can say which half is past and which is present.

What conditionals do in an argument

In Task 2 you do three jobs with conditionals.

State a consequence. “If governments subsidise public transport, more commuters will leave their cars at home.” The first conditional is the working structure of a cause and effect paragraph, and fits the problem and solution and two-part question types. See the guide to problem and solution essays.

Make a hypothesis. “If schools ended exams, pupils would study for interest rather than marks.” The second conditional lets you test an idea that is not true now.

Recommend an action. “If I were in charge of the budget, I would spend more on rail.” This is the voice of a recommendation, and it sits well at the end of a paragraph.

Conditionals also soften claims. “If this trend continues, the gap may widen” is more defensible than “The gap will widen”, because the claim depends on a stated condition. The guide to complex sentences covers the other conjunctions that make such links, and the guide to the Writing test format shows where each task asks for an argument. In Task 1, conditionals have little use because you describe what a visual shows, not what might happen.

Conditionals in Speaking Part 3

The second conditional is the natural structure when the examiner asks what might happen: “If more people worked from home, I think traffic would be lighter.” The first conditional works for likely outcomes: “If the cost of living keeps rising, young people will move out later.”

Keep the sentence short enough to finish, since an abandoned if-clause costs fluency as well as grammar, and pick one type before you begin: starting with “If I had…” and finishing with “I will…” mixes two types by accident.

Other ways to express a condition

“If” is not the only word. These alternatives suit writing and are often more precise.

“Unless” already contains the negative, so “Unless you do not revise” is wrong. Inversion with “should” or “had” (“Had the council acted sooner, …”) is formal and correct, but optional, and only worth using if you can control it.

The common errors

“Will” in the if-clause

• Wrong: “If the government will raise taxes, people will spend less.”
• Right: “If the government raises taxes, people will spend less.”

“Would” in the if-clause

• Wrong: “If cities would build more parks, residents would be healthier.”
• Right: “If cities built more parks, residents would be healthier.”

The wrong pairing

The second conditional pairs past simple with “would”, the third pairs past perfect with “would have”. Crossing them is correct only when the two times really differ, as in the mixed conditionals above; crossed by accident, the forms break.

• Wrong: “If she would have a degree, she would get the job.” (“would” in the if-clause)
• Right, second: “If she had a degree, she would get the job.”
• Right, third: “If she had had a degree, she would have got the job.”

A double negative with “unless”

• Wrong: “Unless the law does not change, …”
• Right: “Unless the law changes, …” or “If the law does not change, …”

A first conditional for an imagined situation

• Wrong: “If I will be a bird, I fly.”
• Right: “If I were a bird, I would fly.”

If the situation is imagined, it needs the second conditional.

Why accuracy comes first

Both halves of a conditional have a fixed form, so an error is easy to see. The descriptors’ idea of range is a variety of structures used with control, not a count of how many you tried. First and second conditionals are enough for nearly every argument; keep the third and mixed forms for when the meaning demands them.

To practise, take three claims from a recent essay and rewrite each as a first conditional, then as a second if it can be a hypothesis. Check that the if-clause has no “will” or “would”, and read each aloud to be sure you can finish it. The guide to common Writing mistakes lists other errors to check in the same pass.