That is how this book is arranged.
Part One — the twelve tenses, one chapter each. The shape in three lines, what the tense really means, four situations that call for it, six ordinary sentences, the three mistakes people actually make with it, and — the section worth reading if you read nothing else — the tense it gets confused with, put side by side in one pair of sentences that mean different things.
Part Two — one hundred situations. A situation in one line, the sentence you should write, the name of the tense, why it is that one, and the version you would be tempted to write instead, with what that version would actually mean.
That last part is the whole method. Most tense mistakes are not nonsense. They produce a perfectly good English sentence that says something you did not intend, which is exactly why nobody corrects you and why the mistake survives for years.
Part Three — sixty pairs that differ by one word. They have been married for forty years and they were married for forty years differ by one word, and one of them says somebody has died. I have lost my keys and I lost my keys. When I arrived he left and when I arrived he had left. Sixty of them, each with what both versions mean.
And at the back, the four pages you will keep coming back to:
• The five questions that choose a tense, in order — work down them and you will land on the right one almost every time
• The thirty-two signal words that decide the tense for you: since, yet, ago, by, while, as soon as
• The verbs that have no -ing form, which removes a whole family of mistakes at once
• The ninety irregular verbs in the only three forms that matter
If your time is short, read four chapters. The present simple, the present perfect, the past simple and the future with will between them cover the overwhelming majority of everything anybody says or writes.
12 tenses · 100 situations · 60 pairs · 90 irregular verbs