These two words are confusing because they sound the same and sometimes the meaning is similar.

Passed is almost always a verb.

Miranda drove past me on the highway. (Drove is the verb)

Miranda passed me on the highway. (Passed is the verb)

past

(adjective): Stanley is past president of the organization.

I’ve been preoccupied these past few months.

(preposition): I’ll meet you at half past five.

Walk past the statue in the center of town and you’ll find the theater on your right.

(noun): In the past, a quorum was sufficient; now, all members must be present.

Ask her about her past.

(adverb): Months went past but no letter came.

I was sitting on the porch when Alan walked past.

passed

(verb): The teacher passed out the exam.

He passed out after the party.

She passed by me without saying a word.

The measure passed without objection.

Joe passed a bad check and was arrested.

Passed can be used as a noun referring to those who have “passed away” (“Say a prayer for the passed”) and as an adjective in games and sports (e.g., a passed ball), but passed is most commonly used as the past tense of the verb to pass.