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What should you do when your portfolio is complete? One possibility is to just do nothing, and it's a great option. But I like to keep an eye on the news, and think about whether it changes my mind on the buy/sell status of each holding.

So here's a look at some of our shares that have been in the news recently:

Vodafone
One of the reasons I like Vodafone Group (VOD 0.93%) (VOD 0.72%), in addition to that juicy dividend yield of 5%-6%, is its international status, and that's helped the company to some very nice new contracts.

After February's deal to provide German giant ThyssenKrupp with mobile phone services, Vodafone went gone on to land a 10-year contract with the New Zealand police force early this month. And last week, a partnership was agreed with Poland's Polkomtel to extend international services to the 14 million users of its "plus" brand.

Fresh reports, in The Sunday Times and other papers, have been surfacing over the potential sale of Vodafone's 45% stake in Verizon Wireless to Verizon. I'm not sure about that, because I like the dividend that Vodafone gets from Verizon -- but a sale could net shareholders a bumper special dividend. We'll see, but at 183 pence, Vodafone remains a firm buy for me.

Tesco
I'm pretty happy with Tesco (TSCO -0.46%) as well, as the share price has responded well to the management's turnaround strategy, reaching 376 pence today. Earlier this month, the U.K.'s biggest supermarket announced the purchase of the Giraffe restaurant chain, bagging 49 restaurants for a little under 49 million pounds.

Such diversification might upset some, but Tesco has prospered through innovation and has pretty much driven the evolution of supermarket shopping in the U.K. I think this is a good deal, and I reckon opening more of these family friendly restaurants in its bigger stores will help keep shoppers inside for longer. Tesco is certainly still a buy.

BP
In 2003, BP (BP 0.49%) invested $8 billion in its 50% share of the newly formed TNK-BP, and last week announced its attention to sell that stake to the Russian state oil company Rosneft. BP will get $12.5 billion for it, and will return the equivalent of the original $8 billion to shareholders.

BP has disposed of assets in order to raise the cash needed for its Gulf of Mexico disaster costs, and is still in negotiation regarding some claims that are possibly inflated or even faked. So, I think I'd have been happier for BP to hang on to the TNK-BP cash until all compensation claims are settled. But with today's price of 459 pence putting the shares on a forward P/E of only 8 and with a 5% dividend yield expected, I'm still happy this is a buy.

Rio Tinto
The Rio Tinto (RIO 0.17%) price fall, to 3,125 pence, has been a disappointment, after fears for the future of iron ore prices sent mining shares sliding. But commodities prices are cyclical, and what goes down must come up, right? At least, in the long term, demand for metals and minerals just has to be strong.

And in the meantime, we have dividends -- Rio Tinto went ex-dividend with respect to its final dividend of 60.34 pence per share on March 6. It, too, is still a buy for me at these prices.

Finally, my idea of the kind of shares that should make up the core of a beginner's portfolio is the same as my choice for an ISA, or a retirement portfolio -- or in fact, any portfolio. I'd start with good strong companies that should stand the test of time and potentially reward you for decades.

Not surprisingly, the Fool's top analysts think similarly, and they have just put together a special report detailing five blue-chip shares which I think would be ideal for anyone at the start of their investing career.

But it will only be available for a limited period, so click here to get your hands on these great ideas that could start you on the road to long-term riches.

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