English & Spanish grammar, explained properly

Look it up once. Understand it for good.

929 reference guides across 12 topics — each one with the rule, the examples, the mistakes people actually make, and practice to check you have it.

583 guides

English Grammar & Writing

Parts of speech, tenses, punctuation and the usage questions that send people to a search box — adverbs, prepositions, antonyms, figures of speech.

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346 guides

Spanish Grammar & Vocabulary

Conjugation, the past tenses that trip up every learner, and the vocabulary you need in the order you actually need it.

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Every topic in the library, largest first.

Worth reading in full

Longer guides that go past the rule into why it behaves that way.

Recently published

The eight most recent additions to the library.

Rule, convention, or somebody's preference

A great deal of what gets taught as grammar is style preference wearing a stern face. Where a point is genuinely disputed, the guide says so and explains both positions rather than quietly picking one.

Examples that earn their place

Every rule is shown in a sentence, and every sentence is checked for whether it actually demonstrates the point it claims to. The tables exist so you can scan for the case you have rather than read to find it.

Corrected when wrong

We publish a lot, about a subject where people care about precision, so some of it will be wrong. Reader corrections are acted on, and each guide carries the date it was last checked.