Error catalogues

Common grammar mistakes and how to fix them

YabLab checks writing in four languages. Pick the one you are learning — each catalogue lists every rule the checker detects, explains in your language and drills. Want the rule before the mistakes? Start with the grammar topics below: each one explains a question learners search for and links to the typical mistakes around it.

• 🇺🇸 English mistakes 95 rules
• 🇷🇺 Russian mistakes 72 rules
• 🇩🇪 German mistakes 97 rules
• 🇪🇸 Spanish mistakes 124 rules

Grammar topics explained

• Present simple vs present continuous: when to use each
• Present perfect vs past simple: when to use each
• Irregular verbs: past simple vs past participle
• Passive voice: how to form it and when to use it
• A, an or the: how to use English articles
• Prepositions: in, on, at and the ones that follow verbs
• Much vs many, some vs any: how to talk about quantity
• Modal verbs in English: can, could, must, should and the rest
• Will vs going to: how to talk about the future in English
• Gerund vs infinitive: -ing or to?
• Comparative and superlative adjectives: -er or more?
• Phrasal verbs: what they are and how to get the particle right
• Russian cases: what the six cases do and when to use them
• Perfective vs imperfective: choosing the verb aspect in Russian
• Russian verbs of motion: идти vs ходить, ехать vs ездить
• Russian verb conjugation: first and second conjugation endings
• Ser vs estar: when to use each in Spanish
• Preterite vs imperfect: when to use each in Spanish
• Por vs para: how to choose in Spanish
• Spanish subjunctive: when to use it
• Spanish direct object pronouns (lo, la, los, las)
• Spanish accent marks: when to write them
• Saber vs conocer: which “to know” to use
• Stem-changing verbs in Spanish (e→ie, o→ue, e→i)
• Irregular preterite verbs in Spanish
• Der, die or das: how to tell German noun gender
• German adjective endings: which ending when?