A beneficial discovery
I think the most beneficial discovery in the last 100 years was "Wechat". Wechat is pretty useful in China. We can use Wechat to text each other and face time. If you so boring, you can send message to you friends and wait for their answer. You can post your photos on Wechat everyday. you can learn some thing important in Wechat. You also can talk to your teacher, maybe is ask homework or when we have test. you also can order some thing like flowers shoes clothes and phones. you also can use your phone to call the taxi. you can use Wechat to pay money for food clothes shoes and so on. you can use it to listen to music. In China, every one use Wechat to do some important things. I usually use it to buy food. because it maybe more cheap for this food.