1.時間を表す by

1 〜までに(は)

I must finish a lot of homework by ten.

He said to me, “I will call you by seven tomorrow.”

Please return these books by Wednesday.

I have to pay back the loan by tomorrow.

I’m going there by the evening.

until との違い

by が「完了」を表すのに対し、untli は「継続」を表します。


○ He should be home by three.

× He should be home until three.


× I must study English by five.

○ I must study English until five.

2 〜の間に

during と同じ意味で使われることがあります。

We work by day and sleep by night.

You should go back home by daylight.

2.場所を表す by

1 〜のそばに、〜の近くに

There is a tree by my house.

She is sitting by the door.

He lives by Tokyo Tower.

near との違い

by と near は共に「〜の近く」の意味ですが、by のほうがより近いことを表します

・I want to buy a new house by the station.
・I want to buy a new house near the station.

by を使ったほうが「駅に近い」ことを表します。英文自体は両方正しい文です。

ただし、後に地名が続く場合は near しか使えません

○ I want to live near Tokyo.
× I want to live by Tokyo.

3.手段を表す by

by を使って手段を表す場合、基本的に by に続く言葉に冠詞はつきません

1 by+交通手段

I will go to Osaka by plane.

He went abroad by ship.

Let’s go to Odaiba by train.

I go to school by bus.

She went back to the hotel by taxi.

My father goes to work by subway.

He went to the bookshop to buy some magazines by bicycle.

We went to Biwako by bike.

I want to go there by car.


I must go there by an early train.

She came home by a late bus.

I go to Tokyo by the 8:30 plain.

交通手段を表す場合、by 以外に on と in も使います。
「車、タクシー」は in
・「バス、自転車、バイク、電車、飛行機、船」は on


「by か on」または「by か in」のどちらも使える場合、どちらかでないといけないルールはありません。
しかし、交通手段を言う場合は by を使うほうが一般的です。

I go there by car.
I go there in a car.

He went to the station by taxi.
He went to the station in a taxi.

Let’s go to Shinjuku by bus.
Let’s go to Shinjuku on a bus.

She goes to school by bicycle.
She goes to school on her bicycle.

He goes to work by bike.
He goes to work on his bike.

My father goes to work by the 7:10 train every morning.
My father goes to work on the 7:10 train every morning.

I went to Okinawa by the 8 o’clock plane.
I went to Okinawa on the 8 o’clock plane.

I’m going to America by ship on January 1.
I’m going to America on a ship on January 1.

2 by+運搬・伝達手段

I’ve sent the baggage by air.

My household goods came by ship.

She’ll go back from Tokyo to Nagoya by air.

I want to go to Hokkaido by land.

He came back to Japan by sea.

Please tell me about it by e-mail as soon as possible.

I knew the truth by letter.

He’ll tell us the information by fax.

I want to send this lette by airmail.

I knew the death of my father by telegram.

3 by+その他の手段

I want to buy it by creditcard.

When I was young, I read books by candlelight.

4.方法・理由を表す by

1 by+doing


He caught the train by running.

She has lost her weight by walking.

He was absent from school by catching a cold yesterday.

I’ve got the highest marks on the math examination by studying hard.

My mother removed all spots from my uniform by washing with her hands.

My shoulders are stiff by reading a book for ten hours.

5.単位を表す by

by の後に「時間、重さ」などの単位が続きます。

I get paid by the hour.

He earns money by the day.

You can rent a car park by the month.

The company pays by the commission.

That supermarket sells meat by grams.

Eggs are sold by the dozen.

6.差異を表す by

by の後には具体的な数字が続きます

A consumption tax will go up by 5%.

A price of beer will go down by 30 yen.

I missed the train by 5 seconds.

He broke his record of a short-distance race by 0.2 second.

比較級での by

比較級は二つの事柄を比べますが、その差異は by を使って表します。
比較級の直前に by を使わずに差異を置く表現もあります。

I’m younger than she by two years.
I’m two years younger than she.

Tokyo was hotter than Hokkaido by 10 degrees celsius yesterday.
Tokyo was 10 degrees celsius hotter than Hokkaido yesterday.


7.乗法と除法の by

掛け算と引き算に by が使われます。

〜 multiply by …(〜掛ける…)

10 multiplied by 3 is 30.

1 multiply by 1.

〜 divide by …(〜割る…)

25 divided by 5 is 5.

100 divide by 20.

同じ分類(上級前置詞)の英文法 単元一覧