【简答题】基准物质指______,能作为基准物质的试剂必须具备以下条件: ①______;②______;③______。
【简答题】食物中的三大供能物质是__________、__________、__________。其中主要的供能物质是__________,重要的储能物质是__________。
【简答题】沉淀滴定曲线的 pCl 与 pAg 两条曲线以 对称。
【单选题】— Must I go to the gym three times a week? — No, you _____. Twice a week is OK. [ ]
【简答题】How often do you do your ______? I go to the gym three times a week.
【判断题】In my spare time, I go shopping, I go to the gym, just hang out with friends."go to the gym" means 去健身房 .
【单选题】How often do you go to the gym to work out?
A.
I often go to the gym.
B.
I go to the gym sometimes.
C.
I prefer to stay at home watching TV than going to the gym.