English grammar · Intermediate

Commonly Confused English Words

Commonly confused words are pairs that look like they should be interchangeable but are not: like and as, try to and try -ing, fewer and less, lie and lay. They are less about rules than about small differences in meaning or grammar, which is why they survive into advanced English.

What it is

A confusable is a pair (or trio) of words that share a meaning zone but differ in grammar, register, or nuance. The confusion usually comes from one of three places: two English words map onto one word in the learner's language (like and as), one form has two meanings (try to and try -ing), or the words sound alike (affect and effect).

She works like a machine (comparison to something she is not). She works as a nurse (her actual job). One letter, different structure, different meaning.

How to spot it

When two words seem to mean the same, check what follows each. Like takes a noun; as takes a clause or names a role. Try to takes an effort; try -ing takes an experiment. The grammar after the word is usually the tell.

  • like a professional (like + noun phrase: comparison)
  • as a professional (as + role: what someone actually is)
  • as I said (as + clause: in the way that)
  • try restarting it (try + -ing: an experiment to see if it works)

In informal speech like is increasingly used before a clause (like I said). It is common and understood, but as is the safer choice in writing.

Confusing Words Quick Reference

Confusables at a glance

PairFirst wordSecond word
like / ascomparison: swims like a fishrole or manner: works as a chef, as I said
try to / try -ingmake an effort: tried to open itexperiment: tried turning the key
fewer / lesscountable: fewer peopleuncountable: less noise
lie / layno object: lie downtakes an object: lay the table
affect / effectverb: it affected menoun: it had an effect on me
say / tellno person needed: she said (that)...person needed: she told me (that)...
borrow / lendtake temporarily: can I borrow a pen?give temporarily: can you lend me a pen?

All 1 confusing words lesson

This section grows as the library does. Each page takes one pair, gives the meaning of each half, shows the grammar that follows it, and then works through the sentences where learners choose wrong. Where a confusable belongs more naturally to another section (fewer and less under quantifiers, -ed and -ing adjectives under adjectives), it lives there and is linked from here.

  • Like vs. As: Like and as both introduce comparisons, but they belong to different word classes. Like is a preposition and is followed by a noun, pronoun, or -ing form: He swims like a fish. As is a conjunction when it introduces a clause (Do it as we practised) and a preposition when it names a role or function (She works as a midwife). Mix the two and you change the meaning: like a coach compares manner; as a coach names the job.

Browse the full English grammar library

Confusing Words FAQs

What is the difference between like and as?
Like compares one thing to another that it is not: he sings like an angel. As introduces a real role or a clause: he works as a teacher, do as I say. In the comparison sense, as needs a clause with a verb (she cooks as her mother did), while like takes a plain noun (she cooks like her mother).
Does try to mean the same as try -ing?
No. Try to plus infinitive means make an effort to do something difficult: I tried to lift the box but it was too heavy. Try plus -ing means do something as an experiment to see whether it solves a problem: I tried lifting the box from the other side, and it moved. Stop, remember, forget, and regret shift meaning in the same way.
Is it fewer or less?
Fewer for things you can count (fewer cars, fewer mistakes), less for things you cannot (less traffic, less noise). Less is also used with numbers seen as amounts: less than ten minutes, less than fifty pounds. The supermarket sign ten items or less is technically wrong and completely normal.
What is the difference between say and tell?
Tell needs a person as its object: she told me the news, tell him to wait. Say does not take a person directly: she said the news was good, she said hello (to me). Tell also carries the fixed expressions tell the truth, tell a story, tell the time; say goes with say sorry, say a word, say goodbye.
How can I stop confusing words that sound the same?
Anchor each one to a structure rather than a translation. Affect is a verb, so it has a subject doing something: the weather affected the match. Effect is a noun, so it follows an article or adjective: a big effect. Meeting the words repeatedly in real sentences, rather than in lists, is what eventually makes the right one feel right.