読む and 読書: What is read and the reading activity
Compare reading a book or letter with reading books as an activity. Identify the object, repeated reading, and time spent reading without imposing a required silent or aloud method.
The verb has something to read
読む means to read. Its stated object can be a book or a letter, so the verb does not restrict every act of reading to books.
「昨日届いた手紙を何度も読んだ。」 (I read the letter that arrived yesterday several times.) The item that arrived yesterday is a letter, and the repeated action is reading that letter. It does not become an account of reading several books.
Book reading named as an activity
読書 names the activity of reading books. The example of reading for about thirty minutes before bed identifies an activity and its duration, without giving a number of books or an amount of understanding.
「静かな午後を読書で過ごした。」 (I spent a quiet afternoon reading.) This says how the afternoon was spent. Its quiet setting does not make quiet surroundings a requirement for every instance of reading.
The object and the activity can overlap
「寝る前に本を読む。」 reports reading a book before bed. It states the object of the verb, while 読書 can name the same book-reading activity. The separate repeated-reading example has a letter as its object.
Look for the book or letter that is the verb's object and the activity named 読書. Neither term alone fixes whether the reader uses a voice or reads silently.
What should you compare between reading a letter several times with 読む and spending time on 読書?
Show the answer and why
Identify the object and repeated action in the first case: a letter was read several times. In the second, identify book reading as an activity and the time spent on it. Reading a book with 読む can overlap with 読書, but the letter example does not become book reading or specify a compulsory reading method.