His aunt Polly stood surprised a moment, and then broke into a gentle laugh.

“Hang the boy, can’t I never learn anything? Ain’t he played me tricks enough like that for me to be looking out for him by this time? But old fools is the biggest fools there is. Can’t learn an old dog new tricks, as the saying is. But my goodness, he never plays them alike, two days, and how is a body to know what’s coming? He ’pears to know just how long he can torment me before I get my dander up, and he knows if he can make out to put me off for a minute or make me laugh, it’s all down again and I can’t hit him a lick.

===================

Got these notes from ChatGPT and Internet:

Modern alternatives for "Someone broke into a gentle laugh":

If you want it to sound neutral:
→ She started to laugh softly.

If you want a small, warm laugh:
→ She let out a little laugh.

If you want something gentle:
→ She gave a soft laugh.

If you want a quiet amused tone:
→ She chuckled.

If you want mild amusement:
→ She laughed a little.

If you want to show she couldn’t resist laughing:
→ She couldn’t help but laugh.
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Modern alternatives to “Hang the boy!”

“Damn the boy!” → The literary modern version.
“That kid, honestly!” → Casual and conversational.
“Oh, that boy!” → Softer, shows resigned amusement.
“For heaven’s sake, that kid!” → Polite, like the old expression but without swearing.
“Jeez, that boy!” → Everyday American, common in speech.
“Ugh, that kid’s gonna drive me crazy!” → Modern, frustrated but funny.
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“Can’t I never learn anything?”

Here are some sentences in the same style:

Can’t I never get a minute to myself?
Can’t I never have things go my way?
Can’t I never do anything right?
Can’t I ever catch a break?
Why does everything happen to me?
I can’t catch a break!
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But old fools is the biggest fools there is.
Fools are in plural, why don't use "are" the biggest...?
Because Twain was imitating an uneducated or poorly educated person's way of speaking, and in a (Southern US rural) dialect.
https://forum.wordreference.com/threads/old-fools-is-the-biggest-fools-there-is.4015872/
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Can’t learn an old dog new tricks, as the saying is.
“As the saying is” → This is older, a bit formal or storybook-like, found in older texts
“As the saying goes” → This is the modern, standard, and widely used version in English today.
Example: “Actions speak louder than words, as the saying goes.”
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and how is a body to know what’s coming?

What does the structure “be + to + verb” mean?

This structure actually expresses a sense of “must” or “how could someone possibly…”.
For example:

What is one to do?
Meaning: “What is a person supposed to do?” or “What can one do?”

How is a body to know?
Meaning: “How is a person to know?” or “How could anyone know?”

Here, is is part of this idiomatic structure — it’s not from the present continuous tense.
If you remove it, the whole structure breaks down.

-----------------
He 'pears...
The author of Tom Sawyer attempted to reproduce the speech sounds of an uneducated rural boy in the mid-1800s. Unfortunately, one result was that it's difficult to read! (I suspect the same would be true of an uneducated rural mid-19th-century child's speech in many other languages, but that's not our problem here.)

It can sometimes be helpful to read the words aloud. For example, in "he 'pears, "" 'pears" takes on a bit of the vowel sound at the end of "he" so the meaning of "he appears" may be a bit more apparent. You might want to try that, though it won't help all the time.
https://forum.wordreference.com/threads/tom-sawyer-citify-im-a-laying-up-etc.2123007/
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Someone really tormented me → It's correct and understandable, but it sounds a bit formal or literary. You mostly see it in writing or stories.

In everyday American conversation, people usually use more casual expressions:
She really drove me crazy. → very common, conversational, and a bit humorous
She really gave me a hard time. → natural and friendly
She really bugged me. → very casual and informal
-----------------

...before I get my dander up

The old idiom:

• “to get one’s dander up” = to become angry or irritated.

  Don’t tease him — you’ll get his dander up.

This was common in 19th–early 20th century American English, especially in rural or Southern dialects. Writers like Mark Twain, O. Henry, and Steinbeck used it a lot.

Modern English:

Nowadays, people would say things like:

• He’s getting mad.

• He’s getting worked up.

• You’re ticking him off.

• You’re getting under his skin.

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I can’t hit him a lick
More common today:
I can’t lay a hand on him
I can’t touch him
I can’t hit him at all
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