The recommendee is 'experienced', usually works in the laboratory or institution of the recommender, their interaction is frequent and purposeful, and their mutual trust significant.
Perhaps the most important criteria teachers could use to identify and select video to mediate science learning is to be purposeful in their selection and to assess whether the video designers' purposes conflicts with their own as teachers; that is an imperative is being clear about reasons for showing a particular video and knowing how it connects to curriculum goals.
You may have seen them zipping along underground, seeming quite determined and purposeful on their way from this point to that.
Yet they still seemed as purposeful as their deskbound sisters, who walked by in more of those sculpted coats, a sturdy leather bag on the shoulder or a folder (surely containing an iPad) in hand.
On a recent winter afternoon, swarms of office workers, purposeful in their step and comfortably dressed for temperature-controlled comfort, moved through one maze-like mall after another, while the snow howled through concrete canyons above.
Some of our great companies are trying to be more purposeful in their business strategies, and demonstrating a commitment to innovation and high performance – judged by criteria other than rising share prices.
4.54am GMT 25th over: England 97-3 (Ballance 15, Morgan 2 Morgann gets off the mark with a gentle single to long-on and Ballance contributes a couple of his own, meaning that England already look more purposeful with their number five at the crease.
Maybe some marches are more purposeful with their routes, maybe a few more windows get broken in some instances, maybe some stores get trashed - Sunday night's demonstration in Berkeley saw a bunch of banks and a Whole Foods get it.
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"Food is different from other industries because people feel an emotional and cultural connection with it, they want to feel purposeful through their food choices," said Ying. "It builds interconnections throughout so much of our lives that it's much more than just a simple commodity, so we shouldn't treat it that way".
