Question

what a dark night? Change it into assertive sentence

Answer 1

The “dark night of the soul” is a term that goes back a long time. Yes, I have also experienced it. It is a term used to describe what one could call acollapse of a perceived meaning in life…an eruption into your life of a deep sense of meaninglessness. The inner state in some casesis very close to what is conventionally called depression. Nothing makes sense anymore, there’s no purpose to anything. Sometimes it’s triggered by some external event, some disaster perhaps, on an external level. The death of someone close to you could trigger it, especially premature death, for example if your child dies. Or you had built up your life, and given it meaning – and the meaning that you had given your life, your activities, your achievements, where you are going, what is considered important, and the meaning that you had given your life for some reason collapses.

Answer 2

correcting what u asked it should with "!"
ur ans is

It is a very dark night.
u can also write
It is quite a dark night.
info
when converting exclamation to assertive we use very / quite

hope it helps you