阅读下面短文，在空格处填入一个适当的词或使用括号中词语的正确形式填空。

Have you heard of the video﹣ sharing app Douyin? It's quite popular now. There are some  （interest） and useful videos on it.

They are very short ﹣ from fifteen to thirty  （second）. I enjoy watching them. there are some bad things about the app, too.

First, it （take） up too much of our time. You can  （easy） become addicted （上瘾的） to it. Once whole afternoon. I forgot  （do） my homework.

Second, there are a lot of meaningless （无意义的） videos. For example （they） videos on the app. You can't really learn. anything useful by  （watch） these videos.

I just want to tell people that we can learn meaningful things from the Internet. Maybe we shouldn't spend so much timeDouyin.