Grammar & Usage

All 12 English tenses explained with timelines, signals words, and CAT error-correction patterns. Never confuse 'has gone' and 'had gone' again.

Articles (a, an, the) and prepositions (in, on, at, of, by) cause the most small errors in English. This note teaches the rules through patterns, not memorization.

Idioms are phrases whose meaning can't be guessed from individual words. This note covers the 80 most commonly tested idioms in CAT with meanings, examples, and usage.

Build a powerful vocabulary for CAT. This note covers the 200 most important words with synonyms, antonyms, and one-word substitutions organized by theme.