Antonym: beneath, off. Similar words: in, of, oh, ok, one, or, own, son. Meaning: [ɑ /ɒn ,ən] 
adj. 1. in operation or operational 2. (of events) planned or scheduled. adv. 1. with a forward motion 2. indicates continuity or persistence or concentration 3. in a state required for something to function or be effective.
adj. 1. in operation or operational 2. (of events) planned or scheduled. adv. 1. with a forward motion 2. indicates continuity or persistence or concentration 3. in a state required for something to function or be effective. 
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271. He'd never have managed on his own, but his colleagues have pulled him through.
272. This is his centennial year and he's been granted the ultimate accolade - his face on a set of three postage stamps.
273. They rebuilt the house on an even more lavish scale than before.
274. In 1880 Alexander Graham Bell was granted a patent on an apparatus for signalling and communicating called a Photophone.
275. Except for what he spent on haircuts,books and daily necessities he never wasted a penny.
276. The scientists will go on an expedition to the South Pole.
277. I figure life is a gift and I don't intend on wasting it. You never know what hand you're going to get dealt next. You learn to take life as it comes at you.
278. The baby had a plastic name tag on its ankle.
279. On April 19 the new government won a vote of confidence by 339 votes to 207.
280. All in all, I love summer very much! You should start practicing your English from now on.
281. A set of twenty-four carved and gilded chairs appear on the inventory of the house for 1736.
282. Your words fall like acid rain on the wounded petals of my heart.
283. The swinging door is pivoted on one side; the revolving door is pivoted in the centre.
284. Sincere congratulations on your son wedding please convey our best wish.
285. A whole batch of original drawings will be on sale.
286. It is out of question to arrive there on time.
287. We are using up our natural resources and at the same time polluting our environment with dangerous chemicals. If we continue to do this, life on earth cannot survive.
288. You have to reflect on how to answer his questions before you get to his house.
289. The grit beneath her soles grated harshly on the wooden deck.
290. Often there's no clear evidence one way or the other and you just have to base your judgement on intuition.sentencedict.com/on.html
291. He visited me twice that fall and called me on the telephone often.
292. In his lecture, he bore down on the importance of idiomatic usage in a language.
293. I thought I might look in on Bob on my way to the shops.
294. The blood had congealed round the cut on her knee.