In addition to the uses shown below, on is used after some verbs, nouns, and adjectives in order to introduce extra information. On is also used in phrasal verbs such as ‘keep on’, ‘cotton on’, and ‘sign on’. 除下列用法外，on可以用在某些动词、名词和形容词之后引出附加信息。on还可用于keep on, cotton on, sign on等短语动词中。
英英释义
1.in operation or operational
e.g. left the oven on the switch is in the on position
2.(of events) planned or scheduled
e.g. the picnic is on, rain or shine we have nothing on for Friday night
