Hi! Japanese has many pairs of verbs where one verb takes an object and the other does not, such as 始まる (to begin) and 始める (to begin). 始まる is an intransitive verb, and 始める is a transitive verb, which needs an object and object case particle を. .............................. 1. 始める - to begin (transitive) - 彼らは会議を始めた。 (They started the meeting) In order for a verb to be transitive, the subject has to cause an action to happen through its own effort. Which is what happens here since "they" are the ones that "started" the meeting. A clue that this sentence is transitive is that the object affected by the verb is signified with the particle を. .............................. 2. 始まる - to begin (intransitive) - 今日は彼の誕生日のパーティーが1時に始まる。(Today, his birthday party will start at 1 o'clock.) In this case, the action of begin happens on its own without the effort of an outside force and is thus intransitive. A clue that this sentence is intransitive is that event or circumstance that the verb is modifying is paired with the particle が. .............................. Other examples, Jugyō ga hajimaru (授業がはじまる) = the class starts Sensei ga jugyō wo hajimeru (先生が授業をはじめる) = the teacher starts the class are correct, but Jugyō ga hajimeru (授業がはじめる) Sensei ga jugyō wo hajimaru (先生が授業をはじまる) are incorrect, because 始める needs an object, but 始まる cannot take an object. Hope that helps...