This is an simple phone projector that does not require to be plugged in an electric outlet,using the principle of using mirror and biconvex lens to magnifying the image on the phone onto the wall.There is a speaker at the end that does not require to be plugged in an electric outlet as well,it's main purpose is to let multiple people to watch videos together.1) use sth.to do 或 use sth.for doing 所以這里的magnifying,不應(yīng)+ing2) 另外后面一個(gè)using在這里應(yīng)該可以簡(jiǎn)去3）multiple people意思應(yīng)該是更多的人吧,用more people更直接.4）應(yīng)該是let sb.do sth.而不是let sb.to do sth.