で (3)

Particle (Basic ㊦ 107)

A particle (apparently derived from the て form of です) that indicates a weak causal relationship.

Equivalent: And; because of; due to; because

山口さんは病気で学校を休んだ・休みました。: Because Mr. Yamaguchi was ill, he didn't come to school.
明日は期末試験で大変です。: I'm having an awful time because of tomorrow's final exam.
大雨で橋が壊れた。: Heavy rain destroyed the bridge.
昨日は夜、仕事でとても疲れた。: Because of my work I got very tired last night.
父は交通事故で入院しました。: My father was hospitalised due to a traffic accident.

Notes

1. Some of the uses of で3 (such as Key Sentence and Example (a)) are very close to the て form of です. For example, Key Sentence can be paraphrased into two sentences (1a) and (1b):

a. 山口さんは病気でした。
Mr. Yamaguchi was ill.

b. 山口さんは学校を休みました。
Mr. Yamaguchi was absent from school.

And Key Sentence can be considered to be the result of combining the two sentences using the て form of です which basically means 'be ~and'.

2. A noun that precedes で3 expresses something that is beyond human control (such as illness, flood, accident, rain, and fire). It is also to be noted that で3 co-occurs with any noun, if a predicate expresses something that is beyond human control. If the co-occurring predicate expresses something that is controllable, the particle で is no longer で3; it is で2 of means. (⇨ で2) Compare (2a) and (2b) below:

a. 卵でアレルギーになる。
Literally: Eggs cause me allergy. (= I'm allergic to eggs.)

b. 卵でオムレツを作る。
I make an omelette with eggs.

(2a) and (2b) contain a noncontrollable predicate アレルギーになる 'become allergic' and a controllable predicate オムレツを作る 'make an omelette', respectively. Therefore, で in (2a) and (2b) are で3 and で2, respectively.

【Related Expression】

The particle で3 is a very loose marker of cause due to its origin; in contrast, から3 and ので are clear subordinate conjunctions of cause/reason.

(⇨ から3; ので)