题型:问答题 简答题 — You’d better not judge a person _____ his appearance. —I know all the people dressed _____ rags are not beggars.A.in; inB.by; byC.in; byD.by; in 查看答案
题型:问答题 简答题 当我们在口中细细咀嚼馒头时会觉得有甜味,设计如下实验试管实验设计现象1馒头屑加2毫升唾液,充分搅拌,37℃水浴10分钟2馒头屑加2毫升清水,充分搅拌,37℃水浴10分钟(1)这个实验中变量是______(2)把试管放入37℃恒温水10分钟的目的______(3)滴加碘液后,没变蓝的是______号试管.(4)试管中物质没变蓝和馒头在口中变甜的原因是______. 查看答案