早晨花叶上有晶莹的露珠,太阳出来后又消失了,关于“露珠”的形成和消失发生的物态变化是 [ ]
A.熔化,液化
B.汽化,液化
C.液化,升华
D.液化,汽化
答案:D
词汇:根据句意填入一个恰当的单词完成句子。
1. What is your _________way to learn more English?
2. It doesn’t _________if you can’t understand spoken English.
3. Mei often _________mistakes in grammar.
4. Li Hong decided to_________lots of grammar notes in every class.
5. Her English improved when she started lots of_________practice.
如图所示是洛伦兹力演示仪,甲图为没有磁场时电子束的径迹,乙图为施加垂直于纸面的磁场后,电子束运动的径迹,则在乙图中所加磁场的方向是 .(填“垂直纸面向里”或“垂直纸面向外”)