What work can one never finish?

A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

I can prove why 1 = 2

* Lets say y = x
* Multiply through by x xy = x2
* Subtract y2 from each side xy - y2 = x2 - y2
* Factor each side y(x-y) = (x+y)(x-y)
* Divide both sides by (x-y) y = x+y
* Divide both sides by y y/y = x/y + y/y
* And so... 1 = x/y + 1
* Since x=y, x/y = 1 1 = 1 + 1
* And so... 1 = 2

How is this possible?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

Replace the question mark in the picture below.

Looking at the figure given, you will find a square formed with match sticks. This figure comprises five squares. Can you move the matchsticks such that the resulting figure consists of ten squares? Please note that you can drag the matchsticks can't rotate them and have just four moves. How will you do it?

What have one eye but still cannot see?

Why do we preferably have round manhole covers and not square ones?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

using four eights (8) and a one (1) and one mathematical symbol , create the number 100