third idiom is
Play It by Ear
Let's go to the movies, agreed?
Sure. And what'll we do after that ?
Oh, I don't know. Let's play it by ear.
Well, I would like to have a more definite plan of action.
Don't be like that. It's always more fun not knowing what to expect and deciding what to do as we go along.
ومعنى التعبير بالعربي : دع الأمور تمر كما تشاء ( نمضي بدون خطة مسبقة وندع الظروف هي التي تحدد مصير الجولة )
كلية أصول الحب