—______you tell me the differences between these two photos?

—No. They look quite similar, nearly the same.

    Are you a-teenager____ (absorb) in music? If so, I will give you a warning – the music you love could end up making you deaf. More ____(specific), the way you listen to the music you love could make you deaf.

    The problem is .headphones. In the past, we played music out into the air. Then earmuff-style（耳罩式）headphones ____ (invent) and we were able to play music much closer to our eras. Now we have earbuds（耳塞）, which many doctors think are ____ (bad) than older headphones because they play music directly into the eras. Also, earbuds are not as good as blocking outside noise, so people____ use them nay turn the volume ____ to dangerous levels.

    What's the dangerous level? Well, it ____(depend) on how long you are going to listen to the noise. Very, very loud sounds can be dangerous to your hearing. But the scary ____(true) is that even seemingly “normal” noise can be dangerous ____you listen to it all the time.

    Think for a minute about how long you spend ____ (listen) to loud noise with headphones every day. Then do some research. There are resources online telling you what volumes are safe, and for how long.

判断一种物体是不是导体时，我们可用的工具有____。我们利用____把电送到人们需要的地方 ，利用____阻止电流到人们不需要的地方。

不能人工诱导原生质体融合的方法是（ 　 ）