Would you say "He looked outside"?

Question

look 1 /lʊk/ ●●● S1 W1 verb

1 SEE [intransitive] to turn your eyes towards something, so that you can see it

We sneaked out while Jessie’s mom wasn’t looking.

If you look carefully you can see that the painting represents a human figure.

Gina covered her eyes, afraid to look.

look at

‘It’s time we left, ’ Ian said, looking at his watch.

The men all turned to look at her as she entered the room.

look away/over/down etc

Dad looked up from his paper and smiled.

‘We can’t go out in this weather, ’ said Bob, looking out of the window.

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outside

1- not in a room, building or container but on or to the outside of it

I'm seeing a patient—please wait outside.

I stood outside in the corridor, looking through the window.

The house is painted green outside.

2-​ not inside a building

It's warm enough to eat outside.

Go outside and see if it's raining.

The heat hits you as soon as you step outside.

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A man was facing the door, and he was turning his eyes towards the wide open space before him so that he could see it.

Would you say "He looked outside"?

Why some people (non-native English teachers or European people who know English) says this sentence is wrong. They said I have to say "He looked through the door" instead of "He looked outside".

But Google book showed a lot of "He looked outside" phrase in many books.

So, what would native English people say?

Answer 1

You may be getting some advice from people who have learned a very extreme form of "received" English. In general,

He looked outside

is perfectly good English. The preposition "outside" can be interpreted either as a preposition acting as an adverb or as an ellipsis of a prepositional phrase, such as "outside the house," acting as an adverb. In either case, the adverbial sense is to indicate where the subject was looking.

Also in general, prepositions cannot act as the object of verbs. That is not an issue with "look," which is an intransitive verb and therefore does not take an object. But let's consider a verb that can take an object.

The cat wants out

is not, at least not according to the canons of received English, considered grammatical. You should say

The cat wants to go out

where the object is an infinitive, namely "to go," which is in turn modified adverbially by a preposition, namely "out."

However, in my part of the U.S., which was largely settled by Scotch-Irish and Germans,

The cat wants out

is idiomatic.

To sum up,

He looked outside

is grammatical, but some apparently similar forms, like

The cat wants out

might be considered regional or dialectical, and other apparently similar forms, like

The cat loves out

would almost certainly be considered odd at best and, at worst, just plain wrong.

So it makes sense to teach people who are not native speakers to avoid usages of verb followed by a bare preposition. Some cases will be grammatical everywhere; others idiomatic somewhere, and still yet others bizarre everywhere. English is hard enough without trying to teach such nuances. But good for you on picking up that the supposedly invariant rule you were taught is really not as general as it was made out to be.

Answer 2

"He looked outside" is correct. The word "Outside" can function as an adverb, meaning "to (or in) the outside".

You get the adverbal use in examples like

I went outside. I slept outside. I played tennis outside.