Improve the highlighted part of the sentence given below:
Please remind me $of\, posting$ these letters to my relatives.

Improve the highlighted part of the sentence given below.
Will you kindly $open$ the knot?

Improve the highlighted part of the sentence given below:
"$The\, more\, they\, earn,\, more\, they\, spend.$"

Improve the highlighted part of the sentence given below.
There is dearth of $woman\, doctor$ in our state. We shall have to recruit some from the other states.

Improve the highlighted part of the sentence given below.
In fact,if it hadn't been for his $invaluable\, advice$ on so many occasions $I$ wouldn't have achieved anything in life.

Improve the highlighted part of the sentence given below:
He should move on to the next point,and not $harp\, one\, sting\, only.$