Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
雖然是否專注的信號燈很值得參考，但希望能夠讓孩子也能開啟鏡頭，可以增加課堂的互動性。