English spelling can be tricky in many ways.
Homophones – words that sound the same, yet have a different English spelling – can be very difficult for English learners to understand.
Principal vs. Principle
A principal is the head of a school. A principle is a belief or a moral that you feel strongly about.
To, Two, or Too
To is a preposition. Two is the number following one. Too means also.
Foreword vs. Forward
A foreword is the introduction to a book. Forward is a direction.
Knight vs. Night
A knight is a man who served his lord as a soldier in armor. Night is what happens when the day is over.
Bald vs. Bawled
Bald means hairless. Bawled means yelled, or cried.
Mail vs. Male
Mail is what you receive in the post. Male is a gender (men.)
Dear vs. Deer
Dear is a term of endearment for someone you regard with deep affection. A deer is an animal, like Bambi. A deer can be dear to you, but a dear cannot be deer to you.
Eight vs. Ate
Eight is the number following seven. Ate is something you would do for lunch. You can remember that ATE has the same letters of EAT, moved around.
Made vs. Maid
Made is the past tense of make. A maid is a person who does domestic work. It’s spelled like ‘aid’, because it helps!
Information source: http://www.grammar.net/ginger_homophones