Once there was an old man in a town. He always forgot a lot of things. So his wife always had to say to him, "Don’t forget this ! "
One day he went on a long trip alone. Before he left home, his wife said, "Now you have all these things. They are what you need for your trip. Take care of your things during the trip." He went to the station, bought a ticket and got on the train with it.
   About half an hour later, the conductor began to see the tickets. He came to the old man and said, "Will you please show me your ticket?" The old man looked for his ticket in all his pockets, but he could not find it. He was very worried. “I can’t find my ticket. I really bought a ticket before I got on the train." said the old man.
   “I believe you bought a ticket. All right, you don’t have to buy another one," said the conductor kindly. "But how can I know where I’m going? ---I can’t remember my station!" the old man said sadly.

读《珍珠泉》，根据课文内容填空。

那绿得没有一点儿____的蕨草，那____开放着的花朵，给珍珠泉编了个____的花环。

水是那样绿，绿得像是被周围的绿树、绿草____似的。

如图所示的电解槽接入电路后，在t秒内有n₁个1价正离子通过溶液内截面S，有n₂个1价负离子通过溶液内截面S，设e为元电荷，以下说法正确的是（   ）