The meanings of ものだ


Could someone please explain to me the different meanings that ものだ can have at
the end of a sentence ? Here are some examples I understand the general
meaning of, but I don't understand the logic/grammar behind ものだ

>   * 留学したい **ものだ**
>   * 約束は守る **ものだ**
>   * 父は以前はバスで仕事に行った **ものだ**
>   * 生徒はもっと勉強する **ものだ**
>




There are **_four_** basic usages/meanings of the sentence-ending
ものだ/ものです/ものである, etc. In colloquial speech, 「もの」 often changes to 「もん」.

1) Exclamation, deep emotion, surprise, praise, etc.

2) General tendencies and cold facts.

3) Advice based on common sense, customs, etc.

4) Recollection and reminiscence.

The context in which 「～～ものだ」 appears should tell you which usage/meaning it is
being used for. My advice would be to not over-analyze the short phrase 「ものだ」,
which consists only of two words. Instead, try to get used to the usages by
reading a lot and forming many example sentences yourself.

Now, let us take a look at the sentences you have listed.

> 「留学{りゅうがく}したいものだ。」 "I really would like to study abroad."

would clearly be type #1 above. The speaker's wish to go study abroad is
rather strong here.

> 「約束{やくそく}は守{まも}るものだ。」 "People should keep their promises."

would be type #3 because that is common sense.

> 「父{ちち}は以前{いぜん}はバスで仕事{しごと}に行{い}ったものだ。」 "Daddy used to commute to work by
> bus."

Type #4, no sweat. It is about how something used to be done. The key phrase
is 「以前は」 with the **contrastive 「は」**. The father commuted by bus before, but
not anymore.

> 「生徒{せいと}はもっと勉強{べんきょう}するものだ。」 "Students should study harder."

This would be a split between types #2 and #3. A larger context would probably
tell us which one.




There are **_four_** basic usages/meanings of the sentence-ending
ものだ/ものです/ものである, etc. In colloquial speech, 「もの」 often changes to 「もん」.

1) Exclamation, deep emotion, surprise, praise, etc.

2) General tendencies and cold facts.

3) Advice based on common sense, customs, etc.

4) Recollection and reminiscence.

The context in which 「～～ものだ」 appears should tell you which usage/meaning it is
being used for. My advice would be to not over-analyze the short phrase 「ものだ」,
which consists only of two words. Instead, try to get used to the usages by
reading a lot and forming many example sentences yourself.

Now, let us take a look at the sentences you have listed.

> 「留学{りゅうがく}したいものだ。」 "I really would like to study abroad."

would clearly be type #1 above. The speaker's wish to go study abroad is
rather strong here.

> 「約束{やくそく}は守{まも}るものだ。」 "People should keep their promises."

would be type #3 because that is common sense.

> 「父{ちち}は以前{いぜん}はバスで仕事{しごと}に行{い}ったものだ。」 "Daddy used to commute to work by
> bus."

Type #4, no sweat. It is about how something used to be done. The key phrase
is 「以前は」 with the **contrastive 「は」**. The father commuted by bus before, but
not anymore.

> 「生徒{せいと}はもっと勉強{べんきょう}するものだ。」 "Students should study harder."

This would be a split between types #2 and #3. A larger context would probably
tell us which one.

