Passed - past

Note the difference between the homophones passed and past, both pronounced IPA: /pɑːst/.

• Passed is the past tense of the verb to pass - in any of its senses. Some examples are "He passed down the street", "She passed her exams", "Time passed", "The footballer passed the ball" etc.

• Past may be either an adjective, a noun, a preposition, or an adverb. "History is about the past", "I was an expert once - but that was in the past" and "His past will help him to get this job" are examples of past being used as a noun. "Past experience tells us", "The past week has been difficult" and "His past history will help him to get the job" are examples of the use of past as an adjective. "The train leaves at half past ten" and "The village hall is on the left past the church" are examples of the use of past as a preposition. "He walked past five minutes ago" is an example of the use of past as an adverb.

There is a related confusion explained at Pastime - past time.