【简答题】根据短文内容和首字母提示,把所缺单词填写在短文后面相应的横线上,使句意完整。 It's very important for us to keep (1)h______ in our everyday life. Here is some (2)a______ for you. First, you should have healthy diet. Different food helps us...
【单选题】In the U.S., it's ( ) for children to get smallpox shots because the disease no longer exists today.
【单选题】开环控制系统一般又称为步进电机驱动系统,它的主要特征是系统内没有( )装置。
【单选题】It's important for the figures ________ regularly. [ ]
【简答题】根据句意和首字母提示完成句子。 1. I have a toothache, I have to see a d _____ _. 2. —What's the matter with you? —I have a s ______ throat. 3. It's important for us to have a healthy lifestyle, to eat a b ______ die...
【判断题】某种产品的替代品数目越多,其需求价格弹性越大。