こと Expressions

Table of Contents

There’s a lot of こと expressions. For simplicity’s sake, I’m only going to cover the most basic ones here for now; ones that are either easy to understand or common:

たことがある – I have done.
こと – Command
ことだ – Advice
ことか – You don’t even know…
ことに – Emotional Event

Past tense + ことがある

I have done X before
Simple Past Tense Verb +/ことがある

The most common and useful pattern on this page. This pattern is used to say that you have some experience.
Or rather, that you have done something before.

This pattern may rarely appear as ことはない.
ことはない is comparison は so would likely imply something else similar has been done/not done.

Examples

食べたことがあります
I’ve eaten it before.
飲んだことがない
I’ve never drank it before.
やったことがない
I’ve never done it before.
見たことも、聞いたこともない
I’ve never seen or heard of it before.
寿司の店に行ったことはないが、食べたことはある
I’ve never been to a sushi restaurant, but I’ve eaten sushi before.
クマと見たことはないが、食べたことはある
I’ve never seen a bear, but I’ve eaten one.

こと

Command
Dictionary form Verb + こと
Verb ない form + こと

This こと indicates a command of what to (or not to) do.
It’s pretty stiff, so you won’t hear it spoken that much, but you may see it written.
As a command, it is generally from someone in a higher position to a lower position.
The image that comes to mind is a teacher or parent talking to children.
Do NOT use だ or です after this こと。

Examples

もっと勉強すること
Study more.
今日中に読むこと
Finish reading it today.
友達を殴らないこと
Don’t hit your friends.
えんぴつを忘れないこと
Don’t forget a pencil.

ことだ

Advice
Dictionary form Verb + ことだ
Verb ない form + ことだ

ことだ is used to give definite advice. It is a stronger version of したほうがいい.
It is used primarily to strongly and definitely say what the course of action needs to be/should be.
This ことだ should be in response to a question or statement by someone else.
Has a tendency to be used with conditionals like たければ、and まずは.
There is nothing to highlight in the English translations, but keep in mind ことだ here means:
“the best thing” “the first thing” or “the most important thing”.

Examples

友達を作りたければ、まずは殴らないことだ
If you want to make friends, then first don’t hit them.
許してもらいたいなら、まずは謝ることだ
If you want them to forgive you, start by apologizing.
ホテルで働きたければ、まずは敬語を覚えることだ
If you want to work at a hotel, then first learn Keigo.
上手になりたければ、まずは勉強することだ
If you want to get better, then study first.

ことか

Do you know how much I…
どんなに + ことか

ことか emphasizes an extreme degree my essentially saying “I don’t even know”.
It may help to think of this phrase as omitting a final わからない or 言えない.

ことか expresses that something was (done) so much it can’t even be communicated.
It is typically used when a strong emotion is involved, such as surprise, worry, happiness, or sadness.
This こと phrase is also special in that it requires a “how much” type word with it, typically どんなに

Examples

どんなに頑張ったことか！
Do you know how much I tried? (I can’t tell you)
何トン食べたことか
Do you know how many tons he ate?
何回説明したことか
I don’t even know how many times I explained it to him.
どれほど泣いたことか
I don’t even know how much I cried.

ことに

Emotional Occurrence
Emotion adjective + ことに

ことに is actually the easiest of the patterns here. It simply marks an occurrence as a “happy/sad/etc. “. It tends to emphasize the emotional aspect of the occurrence.

嬉しいことに, and 残念なことに are the most common patterns.

Examples

嬉しいことに、彼女と結婚することになった
Happily, We’re going to get married.
悲しいことに、その犬は死んだ
Sadly, that dog died.
残念なことに、引っ越すことになった
Unfortunately, I’m going to be moving.