Basics. Expressing Purpose with the To-Infinitive

Expressing Purpose with the To-Infinitive

When we want to explain why someone does something, we often use the to-infinitive (to + base verb). For example, instead of saying, "I went to the store because I wanted to buy milk," we can simply say, "I went to the store to buy milk." It is the most natural way to answer the question "Why?" in English.

In this challenge, you will practice using the to-infinitive of purpose in a variety of fun and bizarre situations. You will help a digital nomad connect to Wi-Fi, explain why a frantic student's cat went to the vet, and decode a secret agent's mission report. You will also learn to avoid common traps, like incorrectly using "for" instead of "to" before a verb.

You'll work through 12 questions in a mix of single-choice, multi-choice, drop-down, and drag-and-drop formats. Try the quiz to check your knowledge!

Infinitive

If you've ever written I enjoy to swim or He let me to go and only later learned why both are wrong — you've hit the infinitive's main puzzle. English is fussy: some verbs demand the to-infinitive, some demand the bare infinitive, some demand the gerund, and a few accept multiple options with different meanings (remember to lock vs remember locking).

The infinitive is the basic form of a verb, used non-finitely. The to-infinitive (to go) follows verbs like want, decide, plan; the bare infinitive (go) follows modal verbs (can, will) and causatives (Let him go).

Past tense

If you've ever told a story in English and felt the timeline get tangled — I came home, the dog ate, the cat slept — you've hit the limits of using simple past for everything. The past tense system has four forms specifically because real stories have layered timing: things that happened before other things, actions caught in progress, sequences of completed events.

The past tense has four English forms: simple past (I walked), past progressive (I was walking), past perfect (I had walked — earlier than another past event), past perfect progressive (I had been walking — ongoing up to a past point). Plus irregular verbs for the simple-past form.

Phrase

If you've ever read a long sentence in English and felt lost in the middle, you've hit a sentence with too many phrases stacked together. Learning to spot phrases — on the table, the man with the hat, very quickly — turns dense prose into something you can parse: each phrase is one chunk of meaning, not a string of unrelated words.

A phrase is a group of words functioning as a single unit in a sentence, without a subject + verb pair (which would make it a clause). Types include noun phrase (the red car), verb phrase (has been running), prepositional phrase (on the table), and adjective/adverb phrases.

Verb

If grammar feels overwhelming, the fix is almost always to focus on verbs first. They carry the action, the time, the mood, and the voice — a single verb form decides whether your sentence reads as past or present, fact or hypothetical, active or passive. Get verbs solid and the rest of grammar suddenly looks much smaller.

A verb expresses action, state, or occurrence — the engine of every English sentence. Most verbs have five forms (base, -s, past tense, past participle, -ing); be has eight; modal verbs have fewer. Verbs carry tense, aspect, mood, and voice.

Simple tense

If you're at A1/A2 and the array of English tenses feels overwhelming, here's the good news: most of what you need to say at the start fits in the simple forms. I work, I worked, I will work — three forms cover habits, completed past actions, and basic future. Master these first; the progressive and perfect come more easily once the simple is solid.

The simple aspect is the unmarked verb form — no progressive -ing, no have + past participle. I go, I went, I will go. Marks single completed actions, habits, or permanent states.

A1 | Elementary | Beginners

If you can say your name, ask Where is the toilet?, and read a simple bus sign — but freeze when someone speaks at normal speed — you're at A1. That's not a problem to fix; it's the level where most learners actually live for a while, and recognising it lets you pick the right material instead of drowning in advanced grammar that wasn't meant for you yet.

A1 is the starting level of the CEFR framework, covering basic everyday communication: greetings, introductions, simple personal questions, present-tense forms of be/have/do, and core determiners and prepositions.

Difficulty: Easy

If a textbook leaves you confused, sometimes the issue isn't the topic — it's that the practice material is layered with extra complications. Filtering by Easy strips that away. You get one rule at a time, in plain everyday language, with no trick questions. It's how you make a shaky foundation solid before stacking more on top.

The Easy difficulty tag marks beginner-level questions and challenges — typically A1 or early A2. Single-rule focus, short sentences, common vocabulary, one clear correct answer.