Explanation
Indicate a state where an action is left as is (unchanged or unfinished).
Formation
Verb-ますstem + っぱなし
Detailed explanation
The ～っぱなし grammar point is used to express that an action happened and was left in that state, unattended or unchanged. It is formed by taking the ます-stem of a verb and adding ～っぱなし.
Examples
窓を開けっぱなしにすると、虫が入ってくる。
Mado o akeppanashi ni suru to, mushi ga haitte kuru.
If you leave the window open, bugs will come in.
洗濯物を干しっぱなしで、雨に濡れた。
Sentakumono o hoshippanashi de, ame ni nureta.
I left the laundry hanging out, and it got wet in the rain.
彼はドアを開けっぱなしにして出かけた。
Kare wa doa o akeppanashi ni shite dekaketa.
He went out leaving the door open.
テレビをつけっぱなしにして寝てしまった。
Terebi o tsukeppanashi ni shite nete shimatta.
I fell asleep with the TV left on.
Practice
Grammar content sourced from hanabira.org.