1. There was a sweetness and softness in the woman’s expression that I had never seen before.

2. There was sweetness and softness in the woman’s expression that I had never seen before.
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Do we have to put 'a' before sweetness or not? Which one is grammatical?

[Amazon Music]

There Was A Sweetness
Frank Bango
From the Album Fugitive Girls
January 1, 2001

sweetness

[noncount]
1: the quality of tasting or smelling sweet
I like the sweetness of the sauce.
2: the quality of being kind or loving
the sweetness of his nature
I'll never forget the sweetness of her smile.
3: the quality of being pleasant or appealing
the sweetness of the melody

So if you think first there was sweetness, and then we evolved to like sweetness, you’ve got it backwards; that’s just wrong. It’s the other way round.

1. There was a sweetness and softness in the woman’s expression.

2. There was sweetness and softness in the woman’s expression.
3. There were sweetness and softness in the woman’s expression.
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Which one is grammatical? Do we have to use 'was' or 'were'?
Do we need to put 'a' as in Sentence 1 or not?

Since this is a poetic expression (in a song), I'd go with "a sweetness…"

Regarding the verb, I'd still stick with #1, but #3 is grammatically correct, too.

Both sentences are grammatically correct, but they have slightly different meanings.

1. "There was a sweetness and softness in the woman's expression that I had never seen before."

In this sentence, the use of "a" before "sweetness" and "softness" suggests that the woman's expression had an overall quality or character of sweetness and softness. It implies that these qualities were new and unique to the speaker's experience.

2. "There was sweetness and softness in the woman's expression that I had never seen before."

In this sentence, the omission of "a" before "sweetness" and "softness" suggests that these qualities were present in the woman's expression, but they are not being described as a distinct character or quality. It simply means that the speaker observed the presence of sweetness and softness in the woman's expression for the first time.

So, whether or not to include "a" depends on the intended meaning and emphasis you want to convey.