What are the differences amongst 「ならびに」, 「かつ」 and 「および」?


In which situations can I choose one of them to use?




# According to a dictionary...

### 1. ならびに

> `ならびに` ([接続]{せつぞく}):
> [二]{ふた}つの[事柄]{ことがら}を[結]{むす}び[付]{つ}けて，[並列]{へいれつ}の[関係]{かんけい}にあることを[表]{あらわ}す。および。また。

(From Daijirin Dictionary)

Translation:

> `ならびに` (Conj.): Used to express that two things are connected and
> linguistically parallel. _Similar_ to `および` and `また`.

### 2. かつ

> `かつ` ([副]{ふく}): 二つのことが[同時]{どうじ}にまたは[相前後]{あいぜんご}して[行]{おこな}われることを表す。
>
> `かつ` (接続): 二つの[動作]{どうさ}・[状態]{じょうたい}が[並行]{へいこう}あるいは[添加]{てんか}して行われることを表す。

(From Daijirin Dictionary)

Translation:

> `かつ` (Adv.): Used to express that two thing are done concurrently or near
> time.
>
> `かつ` (Conj.): Used to express that a thing fulfills two conditions.

# My opinion

### 1. ならびに, および

`ならびに` and `および` are written language usually. And they are also used in
polite and formal speech especially in a scene that someone speaks to
audience. In ordinary talk, `と` or `それと` can be used instead.

In most cases, `ならびに` can be replaced with `および`, `また`, and `さらに`.

Example (On a event in a school, the principal is speaking to audience):

[code]

    [地域]{ちいき}の[皆]{みな}さん、ならびに[保護者]{ほごしゃ}の[方]{かた}におかれましては、ご[足労]{そくろう}[頂]{いただ}きありがとうございます。
    (I would like to thank local residents and parents (of the students) for coming our school.)
    
[/code]

above is equal to:

[code]

    1. 地域の皆さん、および保護者の方におかれましては、ご足労頂きありがとうございます。
    2. 地域の皆さん、また保護者の方におかれましては、ご足労頂きありがとうございます。
    3. 地域の皆さん、さらに保護者の方におかれましては、ご足労頂きありがとうございます。
    
[/code]

### 2. かつ

Daijirin says that `かつ` are used as both conjunction and adverb but I can't
classify how it is used in many sentences. `かつ` can be used in ordinary, speak
or polite language. The certain thing I know is that `ならびに` and `かつ` have
different meanings.

Things and conditions connected with `かつ` are fulfilled at the same time.

Example:

[code]

    [彼]{かれ}は[笑]{わら}い、かつ[踊]{おど}った。
    (He laughed and danced.)
    
[/code]

And also it's used in math / programming. If I want to pronounce `A ∩ B = C`
(Set theory),

[code]

    A かつ B [は]{wa} C
    
[/code]

If I want to pronounce `if(a == b && c == d)` (C programming language),

[code]

    1. もし a イコール b かつ c イコール d なら
    2. もし a は b に[等]{ひと}しく、かつ c は d に[等]{ひと}しいなら
    
[/code]

# Thus

  * `ならびに` and `および` can be used when you want to write polite sentences.

  * `ならびに` and `および` can also be used when you speak to audience.

  * `かつ` can be used when you want to describe two conditions that are fulfilled at the same time.

