The word “past†can be used in different forms of speech. The word past can be used as a noun, adverb, adjective, and preposition. Basically, the word “past†actually refers to a previous happening or occurrence in time, and it can simply be said to mean “past tense.†Let me use “past†in sentences, in its noun, adjective, adverb, and preposition forms, respectively. When it comes to history, think about the past. The movie you just watched now is a past occurrence. I saw her walked past. The time is half-past nine. Now, taking the second word into the study, the word Passed can be used as an adjective and as a verb. It occurs as a verb as the past or past participle tense of pass, which can mean “to walk by or pass by someone, or to exceed or to happen.†For sentence examples, “passed†as a verb: “I passed him when I was coming.†“Passed†as an adjective: “That exam is a passed one for me already.â€