built­in Alexa or from wherever you are using your mobile devices.

　　Amazon Smart Plug

　　*Amazon Smart Plug works with Alexa to add voice control.

　　*Schedule lights, fans, and appliances to turn on and off automatically, or control them remotely when you're away.

　　*It's simple to set up and use. Plug in, open Alexa app, and start using your voice.

　　The Philips Hue White Smart Bulb

　　*It works with Amazon Alexa to support dimming through voice control.

　　*Schedule your own custom lighting scenes. Set the smart bulbs to turn on and off at a pre­set time.

　　*To install, simply screw(拧) the smart bulbs into your desired light location.

　　*Control smart­bulb­equipped lamps and overhead lights via the Philips Hue App.

　　August Smart Lock Pro

　　*It works with Alexa for voice control(Alexa device sold separately)．

　　*Control keyless access. It locks automatically behind you, and unlocks as you approach.

　　*Install in about 10 minutes with just a screwdriver(螺丝刀)．

　　(　　)56. What do the four gadgets have in common?

　　A. Useful Philips Hue App. B. Beautiful lighting scenes.

　　C. Easy installation and simple set­up. D. Pleasant temperature.

　　(　　)57. This passage is intended to ________．

　　A. introduce the gadgets of smart home B. provide advice for home decoration

　　C. compare the gadgets with others D. show the popularity of the gadgets

　　B

　　We've all heard the saying: practice makes prefect! In other words, acquiring skills takes time and effort. But how exactly does one go about learning a complex subject such as tennis, calculus, or even how to play the violin? An age­old answer is: practice one skill at a time. A beginning pianist might rehearse scales(音阶) before chords(和弦). A young tennis player practices the forehand before the backhand. Learning researchers call this "blocking"， and because it is common and easy to schedule, blocking is dominant in schools, training programs, and other settings.

　　However another strategy promises improved results. Enter "interleaving"， a largely unheard­of technique that is catching the attention of cognitive(认知) psychologists and neuroscientists. Blocking involves practicing one skill at a time before the next (for example, "skill A" before "skill B" and so on, forming the pattern "AAABBBCCC"), while in interleaving one mixes practice on several related skills together (forming for example the pattern "ABCABCABC")．

　　Over the past four decades, a small but growing body of research has found that interleaving often outperforms blocking for a variety of subjects, including sports and category learning. Yet there have been almost no studies of the technique in unplanned, real world settings-until recently. New research in schools finds that interleaving produces dramatic and long­lasting benefits for an essential skill: math. Not only does this finding have the potential to transform how math is taught, it may also change how people learn more generally.

Researches are now working to understand why interleaving produces such impressive results. One important explanation is that it improves the brain's ability to tell apart between