①I often browse in a bookstore.
（よく本屋で立ち読みするよ。）
●browse = (本)を拾い読みする
→ in a bookstoreを付加することで, 「立ち読み」を表すことができます。最も一般的に使われるのがこのフレーズです。
※browseは他にも「ネットで閲覧する」という意味もあります。
ネット検索に利用するSafariやInternet Explorer, Google Chromeは「ブラウザー（browser）」って言いますが, browseからきています。
②I sometimes read books without buying.
（購入せずに本を読むことがある。→ 時々立ち読みするよ。）
●「立ち読み」
→「買わずに本を読む」と発想転換し, read books without buying
〇ちなみに…
本屋に行くと「立ち読み禁止」の掲示が貼ってある場合があります。
"NO BROWSING" と書かれてあります。
read without buying =買わずに読む
と表現することができます。
アメリカの本屋さん（Barnes and Noble等）では、カフェが併設されており、多くの人がコーヒーを片手にread without buyingをしています。（本を買わずにカフェに持ち込んで読み、終わったらまた元の売り場に戻す行為）気に入ったら購入する、日本の立ち読みと同じです。
I often browse the bookstore reading books before I buy.
"browse/ peruse" means to look around or search without a specific goal. Often in a bookstore this means you read a bit of the book before you buy it, so as to make sure you want to buy that book.
If you are the owner of a newsagents or bookshop and people continually read the products as opposed to simply glance at them with an intention of buying, then the products may eventually become damaged and you may well say to such malingerers: "You are soiling the reading merchandise!"
This practice may be very Annoying for the shopkeeper.
However you may say to your friends that you had to wait some time for the train home:
I just killed a couple of hours in a bookshop."
本屋さんや新聞屋さんのオーナーなら、ただ一瞥をくれるだけでなく、人によっては商品を読んでその結果、傷がつくこともあるでしょう。そんな人にこういうと良いでしょう。
"You are soiling the reading merchandise!" 商品が傷つけていますよ！
こういうのは本当に店番しているほうからすると嫌ですよね。
友達にはこう伝えることもできます。家に帰る電車を待っていなくちゃいけないんだと。
例：I just killed a couple of hours in a bookshop."
Browsing is the act of not buying a book and reading at a bookstore. It is also used for when you look at websites and read text on the internet, this is called 'internet browsing'.
Perusing / poring over. "just bowsing" ..is more about shopping for stuff!
I was often found perusing books I had little intention of buying.
"I like to spend time in bookshops perusing the latest titles..."
Often we simply want to "kill some time" (idom) and a good way to to do that may be to spend time wandering around a good comic store or book shop..
just checking out what the new titles are...
"I like to spend time in bookshops perusing the latest titles..."
（本屋で新作を探しながら過ごすのが好きです。）
私たちは頻繁に"kill some time" (”時間を潰す”) 事があり、そうした場合に本屋さんをうろちょろするのが良い時がありますよね。
どんな新刊が出ているのかチェックしてみたり。
I often read books in the bookstore without buying them.
I often just browse at the bookstore.
To read without buying.
We can simply say that you are, "reading without buying," however the two top examples give you more of a full sentence to say and explain the action a bit further. We can use the verb, "to browse," to mean that you're looking and maybe considering what books you might want to buy without actually buying them.
日本 
アメリカ合衆国 
南アフリカ 
イギリス 
