Improve the highlighted part of the sentence given below.
This matter $admits\, of$ no excuse.

Improve the highlighted part of the sentence given below.
This telephone number $is\, not\, existing.$

Improve the highlighted part of the sentence given below:
He could not $look$ anything in the dark room.

Improve the highlighted part of the sentence given below.
They are social insects, $living\, in\, communities$, regulated by definite laws, each member of society bearing a well-defined and separate part in the work of a colony.

Improve the highlighted part of the sentence given below.
As she was suffering from high fever,she could not $face$ the examination.

Improve the highlighted part of the sentence given below.
The demonstration $passed\ off$ peacefully.