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Education Concept Tracker

A prerequisite knowledge graph of 1590 learning concepts across 8subjects. Track what you've mastered and see exactly what you're ready to learn next — the topics whose prerequisites you've already met. Built on the Marble Open Skill Taxonomy.

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Knowledge-graph map

Computing
Mastered Ready to learn LockedHover a node for its description · click to open
Computers in Everyday L…Computers in Everyday Life — frontier Identifying computers in everyday life — not just laptops but phones, tablets, smart speakers, traffic lights, washing machines; what makes something a computerReal-World RobotsReal-World Robots — locked What a robot really is — not the sci-fi version; robots in factories, robot vacuum cleaners, robot arms in surgery; that robots follow instructions given by peopleSmart Versus Not-Smart…Smart Versus Not-Smart Devices — locked Sorting objects into 'smart' (can sense and respond) and 'not smart' (just sits there); a toaster vs a smart speaker; introduction to the idea that some machines can sense and respond to the worldStep-by-Step Instructio…Step-by-Step Instructions — locked Step-by-step instructions for everyday tasks (making a sandwich, brushing teeth); that if instructions are wrong or missing, things go wrong; computers follow instructions exactly
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The Present Perfect Tense

English · Grammar & Punctuation · conceptual

Use the present perfect form of verbs in contrast to the simple past tense, understanding how the present perfect indicates an action completed at an unspecified time or with ongoing relevance (e.g., 'He has gone out' vs 'He went out')

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What mastery looks like

  • Form the present perfect using 'has/have' + past participle (e.g., 'She has eaten', 'They have finished')
  • Choose between simple past and present perfect to match the intended meaning (e.g., 'I ate lunch' vs 'I have eaten lunch')
  • Identify the present perfect form in a text and explain why the author used it instead of simple past

Check your understanding

Can The Present Perfect Tense explain the difference between "I ate breakfast" (simple past) and "I have eaten breakfast" (present perfect) — knowing one means a finished action and the other links the past to right now?

Prerequisites

Required first

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