Anatomy of a Conditional Sentence
A conditional sentence consists of two parts — clauses:
- the if-clause — the condition;
- the main clause (result clause) — what follows from the condition.
If the migration fails, we roll back automatically.
└──── if-клауза ────┘ └──── главная часть ────┘
Neither part lives on its own. If the migration fails leaves the reader waiting; we roll back automatically is grammatically independent but says nothing about when.
The order can be swapped
Both orders are correct and mean the same thing. What changes is the emphasis: whatever comes first is what you are drawing attention to.
| Order | Example | Emphasis |
|---|---|---|
| Condition first | If the migration fails, we roll back automatically. | on the risk |
| Result first | We roll back automatically if the migration fails. | on the safeguard |
In a status update for the team you would write the first. In documentation describing a feature — the second.
The comma rule
There is one rule, and it is worth learning, because it is mechanical:
if-clause first → comma. Main clause first → no comma.
- ✅ If the build is red, don't merge.
- ✅ Don't merge if the build is red.
- ❌ Don't merge, if the build is red.
- ❌ If the build is red don't merge.
Leaning on Russian. Russian punctuation always puts a comma before «если»: «Не мержи, если сборка красная». English does not: when the condition comes second, the word if itself marks the boundary, and the comma is superfluous. This error persists longest among strong learners — precisely because the Russian rule fires automatically.
Description
Ромб с вопросом «Что стоит первым?». Стрелка «условие» ведёт к блоку «if-клауза: If the build is red, don't merge.», под ним — «ставим запятую». Стрелка «результат» ведёт к блоку «главная часть: Don't merge if the build is red.», под ним — «запятой нет — не переносите русское правило». Схема сводит правило к одному вопросу о порядке частей.
Verb tense is not event time
This is the one idea that opens up the whole course.
Verb tense (tense) is the form: fails, failed, had failed. Event time (time) is when it happens: now, yesterday, next Tuesday.
In conditional sentences the two diverge:
- If it rains tomorrow, the outdoor stand-up is cancelled. — present (rains), but the time is the future.
- If we had more staging capacity, we would test this properly. — past (had), but the time is the present. This is about today's capacity, not last year's.
So what does shifting the tense back express? Distance from reality. Present — what is really possible. Past — what is imagined now. Past perfect — what is imagined in the past, what did not happen.
Description
Раскрытый старый скетчбук на грубом деревянном столе. Левая страница в тёплой акварели: молодая женщина в зелёном джемпере сидит за рабочим столом с ноутбуком и кружкой, за окном дождь. Правая страница нарисована только бледным карандашом, без цвета: та же женщина отдыхает в шезлонге у моря под зонтом, рядом на песке лежит закрытый блокнот. Это ключ ко всему курсу: акварель — реальность («сейчас я работаю»), голый карандаш — воображаемое («If I had a week off, I would be at the sea»). Past simple had здесь про сегодня, а не про прошлое. Рисунок не показывает саму форму глагола — только, что реально, а что нет.
Every drawing in the course works this way: watercolour is reality, pale pencil is the imagined. That is why the type cannot be "read off" the verb form. You have to ask what the speaker is claiming about the world. That — not a table of tenses — is what the course teaches.
The four traditional types
You have most likely met them. They are handy labels for four common cases; the course uses them, but the system does not end with them.
| Name | Pattern | Example |
|---|---|---|
| Zero | if + present, present | If the cache key is missing, the service queries the database. |
| First | if + present, will + infinitive | If we merge today, we will ship on Friday. |
| Second | if + past simple, would + infinitive | If we had a second reviewer, the queue would move faster. |
| Third | if + past perfect, would have + past participle | If we had pinned the version, the build would not have broken. |
And now four ordinary sentences from a working week at ENGAGE that do not fit into any type:
- If the retry succeeded, the alert must have been noise. (inference about the past — u08)
- If the load test passes, deploy to production. (instruction — u03)
- If you assess the data thoroughly, you might find the root cause. (weakened prediction — u07)
- If we had pinned the version, the build would not be broken right now. (cause in the past, consequence now — u06)
All four are normal English. They will come later. They are here only so that you stop expecting a number from every conditional sentence.
What actually changes
Three things, and they change almost independently:
- How real is the condition? — a fact, a likely future, an unlikely hypothesis or the impossible.
- What is the speaker doing? — stating, predicting, inferring, advising, instructing, regretting.
- How sure are they? — will / should / might in the same slot give very different degrees of certainty.
From here the course goes through these three axes one at a time.