When I teach students for whom English is a second (or foreign) language, they often express a desire to practice orally to help them become fluent as quickly as they can.
Less often, one will ask me what book titles I would recommend; when they do, they usually are interested in books on language skills (e.g. ESL textbooks), not books of fiction or poetry, written in English.
An advocate for reading by second language learners, my colleague (and a great ESL teacher, himself) Steve Cavan has recommended the writing of Dr. Stephen Krashen, an expert in theories of language acquisition and development. 
Krashen has published hundreds of books and articles and given more than 500 lectures at universities world-wide to promote the “natural approach” to language teaching. By this he means to encourage students to read recreationally and for teachers like me (and administrators) to ensure that school libraries are well stocked.
Krashen says that “what is good for language development and literacy development is . . . pleasant [to] the acquirer and the teacher.” He has found that time spent free reading is more efficient for developing language skills than the equivalent time spent in traditional instruction.
Reading can (and should) be fun—and can help us learn new languages better.
So many readers and writers find life boring (even or especially in this digital age), when devices can leave us with minds feeling dry, uninspired, even cranky. What Krashen calls the “pleasure path” of reading often lighthearted fiction in a foreign language accelerates our learning of that language.
For instance, Krashen refers to one study in which new immigrants to the US who have progressed very slowly in learning English showed a remarkable spike in progress, due mainly to reading pleasant (potboiler) romance novels, such as the “Sweet Valley High” series. These students were not taking ESL classes at the time. 
My colleague, Steve Cavan, has referred his students to free, online ebooks in English on the following site, where classics have been simplified to levels comprehensible to new learners:
Whether we are new to a language or native-speakers, however, reading deeply, what freelance writer and coach Brad Stulberg calls “full engagement in a book,” can be a joyous experience. When people’s attention spans are shortening by the day (or so it seems), Stulberg says that to be a deep reader “is also a competitive advantage in today’s knowledge-based economy.”
In a recent article in “Forbes” magazine, Stulberg argues that getting lost in a book “is good for the mind and spirit,” allows us to understand topics more deeply, to sustain attention for longer periods of time and to enhance our creativity.
Now, whether for non-English readers or the fully fluent, who would argue against all that?
Stulberg recommends six practices that can help us all read more and read better:
(1) Use a hardcopy book. Research shows that we understand and connect ideas better when we read physical (not digital) pages. There are fewer distractions than with digital media and our brains remember better knowledge acquired through “tactile experience.”
(2) Have no digital devices in the room. Even “the sight of these devices and everything they represent—not to mention the willpower it takes not to check them—is a huge distraction. So find a non-tech room for reading.
(3) Read with a pencil, pen or highlighter. When we engage with books more deeply, actively responding to their ideas, we become more fully absorbed in the material, which improves our “associative thinking and subsequent creative insight.” (This will of course mean that you need to buy the book, which in time means you may wish to donate it to charities, through which others can benefit from it, too.)
(4) Keep a notebook nearby. Even when we’re closely engaged in a book, irrelevant thoughts can pop up in our minds (e.g. groceries to get; errands to run). Stulberg suggests that we right them down in a retraceable place, so that we can “off load [our] brains from trying to hang on to them.”
(5) Read for at least 30 minutes. Deep reading is similar to physical exercise. Our minds are muscles and need to be trained to read over a significant amount of time. Filling in brief moments of your day with an audiobook, though not terrible, cannot compare. 
(6) Read as much as you can. Stulberg rightly says that “books are the best bargain there is” for sharing insights, wisdom and experience. As a professional coach who recommends reading, he has helped Olympic athletes to progress through life, post-sports; business founders through career-defining and challenging times; and has observed that wise leaders “from Bill Gates to Ruth Bader Ginsberg . . . all read a heck of a lot.”
So why shouldn’t we, too? And that’s whether we are new to the English language or not.
And now it’s your turn. Do you practice deep reading in your professional or personal life? Has the thinking of Cavan, Krashen and Stulberg convinced you to get started?
Please share your experience. I’d be delighted to hear from you.