Between Vs. Among

Between is used in connection with two persons or things.
'He divided the money between his two children.'

Among is used for more than two.
'He divided the money among his three children.'

Exceptions:
1. If more than two are involved in a united situation, between is used: 'Between the four of us, we raised a thousand dollars.'

2. If a comparison or an opposition is involved, between is used: 'There was great rivalry between the three colleges. It was difficult to choose between them.'"

Affect Vs. Effect

Affect and effect are two words that are commonly confused.

"Affect" is usually a verb meaning "to influence".
Example: The drug did not affect the disease.

"Effect" is usually a noun meaning "result".
Example: The drug has many adverse side effects.

"Effect" can also be used as a verb meaning "to bring about".
Example: The present government effected many positive changes.

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