As it is: 〜まま

〜まま shows that a state stays unchanged when you'd expect it to change: “as it is, keeping…, without…”. 靴を履いたまま入る: going in with your shoes still on. The state described is often unusual or awkward.

• 靴を履いたまま、畳の部屋に入らないでください。くつをはいたまま、たたみのへやにはいらないでください。Please don't go into the tatami room with your shoes on.
• テレビをつけたまま寝てしまった。てれびをつけたままねてしまった。I fell asleep with the TV on.
• この町は、百年前のままの家が多い。このまちは、ひゃくねんまえのままのいえがおおい。In this part of town, many houses are just as they were a hundred years ago.

まま refers to a state left as it is. After a verb in た, it says the result of the action lasts while you do something else: 眼鏡をかけたまま寝た, “I fell asleep with my glasses on” — English “with… still on”, “leaving… on”.

Often, this state isn't normal: you should have taken it off, switched it off, changed it. まま puts its finger precisely on what hasn't changed.

• 鍵をかけないまま家を出た。かぎをかけないままいえをでた。I left home without locking the door.
• 立ったままご飯を食べるのは、行儀が悪い。たったままごはんをたべるのは、ぎょうぎがわるい。Eating standing up is bad manners.

まま behaves like a noun: it attaches like a noun to verbs and adjectives, then is followed by だ, の + noun, に or で.

• 祖母はいつまでも若いままだ。そぼはいつまでもわかいままだ。My grandmother stays as young as ever.
• そのままお待ちください。そのままおまちください。Please hold the line. (on the phone)

〜ままだ: the state hasn't changed (問題はまだそのままだ). 〜ままの + noun: a noun that's stayed as it was (昔のままの店). 〜ままにする / 〜ままにしておく: to leave deliberately as is. 〜ままで: in that state (このままでいい, “it's fine as it is”).

• 窓は開けたままにしておいてください。まどはあけたままにしておいてください。Please leave the window open.
• このままでは、間に合わない。このままでは、まにあわない。At this rate, we won't make it in time.

〜て simply links two actions (眼鏡をかけて本を読む: I put on my glasses and read). 〜ながら links two simultaneous actions (音楽を聞きながら勉強する). 〜たまま stresses a frozen state that accompanies the action, often an abnormal one.

まま doesn't go after an action in progress: “テレビを見ているまま” isn't said. For two actions at the same time, it's ながら.

• 音楽を聞きながら走る。おんがくをききながらはしる。I run while listening to music.