Dr.Grammar's FAQ's

A lot or Alot?
A lot should be written as two words. Although a lot is used informally to mean "a large number" or "many," avoid using a lot in formal writing.

A or An?
"Use a before a consonant sound; use an before a vowel sound. Before a letter or an acronym or before numerals, choose a or an according to the way the letter or numeral is pronounced.

Accept or Except?
Accept is a verb meaning "to receive" or "to approve."

Except is a preposition meaning "excluding" or "leaving out."
Except can also be a verb meaning "to leave out" or "to exclude."

Affect or Effect?
"Affect is a verb meaning 'to influence.' Effect is a noun meaning a result.' More rarely, effect is a verb meaning 'to cause something to happen.'

All Ready or Already?
All ready means "fully prepared."

Already means "previously."

Allusion or Illusion?
"An allusion is an indirect reference.

An illusion is a misconception or false impression.

Assume or Presume?
"They're not identical. Assume is closer to support, or 'take for granted'; the much stronger presume is closer to believe, dare, or 'take too much for granted.'

Between you and I or Between you and me?
"Because the pronouns following between are objects of the preposition, the correct phrase is between you and me. Yet the phrasing between you and I is appallingly common" (Garner, The Oxford Dictionary of American Usage and Style).