Gerunds vs Infinitives: 7 Rules Every Taiwan Learner Must Know | 英文動名詞 vs 不定詞完整指南

Gerunds vs Infinitives — a grammar point that trips up nearly every Taiwanese learner.

Most grammar problems in English have workarounds. Gerunds and infinitives don’t. If you say “I enjoy to swim” instead of “I enjoy swimming,” a native speaker will notice immediately — it’s not a small mistake. The good news: there are clear patterns behind every choice. Learn the 7 rules below and you’ll stop second-guessing yourself.

Rule 1: What Is a Gerund? [中文: 什麼是動名詞？]

A gerund is a verb ending in -ing that functions as a noun. It can be a subject, a direct object, or the object of a preposition. The form looks identical to the present participle, but the job it does in the sentence is completely different.

• 水泳 is great exercise. (subject)
• She enjoys 読む on weekends. (object)
• He’s very good at cooking. (object of a preposition)

Because gerunds act like nouns, you can replace them with a pronoun: “She enjoys it.” That test works every time — if you can substitute it または this, you have a gerund.

Writing out examples by hand is one of the fastest ways to lock in grammar patterns.

Rule 2: What Is an Infinitive? [中文: 什麼是不定詞？]

An infinitive is to + the base form of a verb. It expresses a purpose, possibility, or the object of a verb. Unlike gerunds, infinitives often point forward in time — toward something planned, wanted, or yet to happen.

• She wants to learn English.
• They decided to move to Taipei.
• It’s difficult to understand fast speech.

Some grammar books talk about “bare infinitives” (without に) — these appear after modal verbs like can, should, will, must. For most learners, the standard to + verb form is what matters.

Rule 3: Verbs That Only Take Gerunds [中文: 只接動名詞的動詞]

These verbs must be followed by a gerund. There is no option — using an infinitive after any of these is an error. The verbs below describe ongoing situations, feelings toward an activity, or actions already in progress or completed.

A memory trick: most of these verbs describe a real, experienced, or completed action — something you can picture happening. Gerunds work with things that feel concrete and done.

Gerund-only verbs are easiest to learn in pairs: enjoy + -ing, finish + -ing, avoid + -ing.

Rule 4: Verbs That Only Take Infinitives [中文: 只接不定詞的動詞]

These verbs are followed by infinitives. Many of them describe plans, wishes, or decisions — things that haven’t happened yet or that involve someone’s intention or will.

When the action is future-oriented — a plan, a wish, a decision — the infinitive is almost always the right choice.

Rule 5: Verbs That Take Both — But With Different Meanings [中文: 兩者皆可但意思不同的動詞]

A small group of common verbs can take either form — but the choice changes the meaning significantly. This is where most English learners, including native speakers of Mandarin, run into trouble.

remember / forget

• I remember meeting her at the conference. → (I have a memory of this past event)
• I remembered to call him. → (I didn’t forget — I did it)
• She forgot sending the email. → (She has no memory of doing it)
• She forgot to send the email. → (She didn’t do it — she failed to remember)

stop

• He stopped smoking. → (He quit permanently — smoking is finished)
• He stopped to smoke. → (He paused what he was doing in order to have a cigarette)

try

• Try adding more salt. → (experiment to see if it helps)
• Try to arrive on time. → (make an effort)

regret

• I regret saying that. → (I’m sorry about something I said in the past)
• I regret to inform you… → (formal opening — I’m sorry to tell you this now)

The pattern is consistent: gerund = backward, referring to the past; infinitive = forward, referring to the present moment or future action.

The stop/remember/try group is the one worth memorizing — they appear constantly in real English.

Rule 6: Always Use a Gerund After a Preposition [中文: 介係詞後面永遠用動名詞]

A verb that follows a preposition must always be in gerund form. No exceptions. This rule applies no matter which preposition you use.

• She’s interested in learning French.
• He’s very good at playing the guitar.
• They thanked me for helping them.
• I’m used to waking up at 6 AM.
• What are you afraid of doing?
• She left without saying goodbye.
• He succeeded in passing the test.

The prepositions most likely to trip you up: about, after, at, before, by, for, in, of, on, without. Whenever you see one of these before a verb, use the gerund automatically.

One common source of confusion: used to + base verb (a past habit — “I used to live in Kaohsiung”) is completely different from be used to + gerund (being accustomed — “I’m used to living in Taipei”). This distinction comes up so often it has its own guide on this site — see Used To, Be Used To, Get Used To.

Preposition + verb = always gerund. Write this rule somewhere visible until it becomes automatic.

Rule 7: The Mistakes Most Taiwanese Learners Make [中文: 台灣學習者最常犯的錯誤]

In Mandarin, the verb 喜歡 (xǐhuān) covers both のように そして 楽しむ. In English, they work differently: のように takes either form, but 楽しむ only takes a gerund.

Another common error: confusing the two meanings of stop. Taiwanese learners who want to say they quit a bad habit often write the wrong structure:

A third trap: the verb 希望 in Mandarin can often be followed directly by another verb. In English, hope only takes an infinitive.

The fastest fix for all three: when you’re not sure which form to use, ask yourself two questions: (1) Is there a preposition before the verb? → Gerund. (2) Is the main verb on the “only gerund” or “only infinitive” list? → Follow the list. For everything else, check this guide.

Running through a few practice sentences each day builds the pattern recognition you need without any memorization.

For deeper practice with English grammar patterns, the guide on conditional sentences covers another set of rules that follow strict form patterns — worth reading after this one. And if verb forms in general are giving you trouble, the irregular verb guide is a useful complement.

The tricky part is that there’s no single logic that explains every case — English borrowed these patterns from Old English and Old French, and the rules solidified over centuries rather than being designed. What that means for learners: the fastest route is not reasoning your way through each sentence but building recognition through repeated exposure to correct examples. The tables and patterns above give you the framework. Practice does the rest.

Quick Reference: Gerund vs Infinitive [中文: 動名詞 vs 不定詞快速對照]

A classroom-style approach — grammar in context — is always more effective than memorizing rules in isolation.

Watch: Gerunds vs Infinitives Explained [中文: 影片說明]

Sources [中文: 參考資料]

1. Cambridge Grammar: Infinitive or Verb -ing? — Detailed rules with examples from Cambridge University Press.
2. Grammarly: What Is a Gerund? — Plain-language overview of gerund function and usage.
3. Oxford Learner’s Dictionaries: Gerund — Reference definition and sentence examples from Oxford.