"The boy asked his dad to read a book."
と has many functions, the one being used here is to encapsulate the phrase before it, either as a spoken phrase, a thought, or a concept. Think of it as putting either quotation marks or parentheses around the previous words.
男の子はお父さんに本を読んでとたのみました。Leave out the longer dialogue and you have 本を読んでとたのみました。
'ほんを読んで' と たのみました。He asked (of his father) , 'Read a book'.
Since there are no actual quotation marks, however, it would be better phrased as translated by Duo.
The te-form conjugation of よむ. Verbs ending in む are conjugated in this way. There are many references online for this.
To add to the answer the other guy gave, it turns the verb "to read" into a command on a request. The boy said to his father "read me a book", which is a request so we use the て form.
I am having a really hard time understanding when to use だ for these...I Think I understand it as being the casual version of です but Duo uses it for some sentences and not for others. Can someone elaborate please?
From my understanding, you use だ when the quote does not end in a verb.
I think that playing the piano is fun --> ピアノを引くのは楽しいだと思います。
I think the food is delicious --> 食べ物はおいしいだと思います。
The sentences end in an adjective, so だ is used.
Close, but I believe because おいしい is an i adjective, it doesn't require the だ.
Some of these questions use the informal form for verbs and some use the て form in regards to verbs for the と particle. Which is it? when I was in class, I was taught the former. I'm pretty sure よむ should be used here, though I only learned about the particle in regards to いう and 思う.
I kinda have an inkling, that as it is a request, that is what the て form is also used for, but at the same time, たのむ is expressing that anyway. Is it purposefully redundant when requesting something? I can't think of any other way to put the て request form in the past tense other than like this.
Anything before と should be considered a quotation. The quote can end in the て form (as a request) or in the dictionary form. Basically, it is saying "The boy asked his father 'read (me) a book'".
Okay so there are roughly four basic parts, three you should be decently familiar with.
男の子は just says it's the boy doing the asking. お父さんに means he's asking his father. たのみました is just the past tense of "to ask".
The last part I assume is what's tripping you up because it acts like a mini sentence. 本を読んで means "read a book" (as an instruction". The particle と turns this into somewhat of a quote, so it makes this mini sentence into what the boy is asking his father.