[Grammar] The meaning of "I should have known better"

[Snappy]

Please tell me if the underlined "with" can be replaced with "about":

"I should have known better with a girl like you" (A Beatle song written by Lennon and McCartney)

Is it common to use "with" in this way? Do you ever say, for example, "I know with it" instead of "I know about it."?

 

[bds51]

Hello Snappy,
No, you don't want to replace (or substitue) 'with' with 'about' because you have a comparison here with 'better'. The complete sentence would be sth like 'I should have known better than to fool around or get interested in or fall in love or get involved with a girl like you. Therefore, 'than to do sth' is understood and leaving it out makes it easier to keep the rhythm. Yes, it's fairly common in some circles to leave out the 'than to do sth' and just say I should have known better with them or simply 'with her, I should have know better.'

To know about is different in your example because there is no comparison. I should have known (more) about her before asking her out. I should have known better than to go out with a girl like her. You should know more about her before you go too far.

 

[Snappy]

Hello Snappy,
No, you don't want to replace (or substitue) 'with' with 'about' because you have a comparison here with 'better'. The complete sentence would be sth like 'I should have known better than to fool around or get interested in or fall in love or get involved with a girl like you. Therefore, 'than to do sth' is understood and leaving it out makes it easier to keep the rhythm. Yes, it's fairly common in some circles to leave out the 'than to do sth' and just say I should have known better with them or simply 'with her, I should have know better.'

To know about is different in your example because there is no comparison. I should have known (more) about her before asking her out. I should have known better than to go out with a girl like her. You should know more about her before you go too far.

Thank you!
Very informative.

 

[Snappy]

I read the lyrics again, and had another question.
"I should have known better with a girl like you that I would love everything that you do."
This line can be paraphrased as "In the case of a girl like you, I should have known better that I would love everything that you do."

Does this mean that "I did not know that I would love everything that girls like you do."?

If yes, can I use "did" instead of "do" in the above sentence?

 

[Raymott]

Does this mean that "I did not know that I would love everything that girls like you do."?
Yes, it does.
If yes, can I use "did" instead of "do" in the above sentence?
Yes, you can.

About 'with', I wouldn't change it either.
Why did we leave the baby with the dog? We should have known better with a pit bull terrier.

 

[Snappy]

Thanks. I didn't know that "know better with" is idiomatic.

Can I say, "Don't trust them! You should know better with such fishy Internet stores."

 

[bds51]

Hello Snappy,
The answer is yes to your two last questions. Even though 'fishy' is correct I'd prefer 'dubious' or 'suspicious' or 'underhanded' or 'dishonest' in your last example.