Questions & Answers about Нужно отпустить прошлое.
Нужно is an impersonal predicative word. In sentences like this, it means something like it is necessary, one must, or it’s needed to.
A key point: it does not change for person or number. Russian is not saying I need or you need directly here. It is more general and impersonal:
- Нужно работать. — It is necessary to work.
- Нужно подождать. — It is necessary to wait.
So in Нужно отпустить прошлое, the idea is general: it is necessary to let go of the past.
Because this is an impersonal construction.
English often uses a dummy subject like it in sentences such as It is necessary to... Russian often simply leaves that out:
- Нужно уйти.
- Важно понять.
- Нельзя курить.
There is no real subject like he, she, or it. The sentence just states necessity in a general way.