一片完全叶包括（ ）
A．叶脉、叶柄、叶片
B．托叶、叶柄、叶片
C．叶脉、叶柄、托叶
D．托叶、叶脉、叶片
答案：B
题目分析：叶是长在茎或枝干上重要营养器官，它有进行气体交换、蒸腾水分和贮藏营养等功能，一片完整的叶子是由叶片、叶柄和托叶三部分构成，桃叶就是这样，人们把它叫做完全叶，桑树、茶树的叶子没有托叶，莴苣、油菜的叶子既无托叶又无叶柄，人们称为不完全叶。
点评：此题为基础题，较易，解答此题的关键是分清完全叶与不完全叶，掌握其结构。
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| A little old couple walked slowly 1 McDonald's one cold winter evening. They looked out of place among the young families and couples 2 there that night. Some of the customers looked 3 at them. You could tell what the admirers 4 ."Look, there is a couple who has been 5 a lot together, probably for 60 years or more!" The little old man walked up to the cash register, placed his order and paid 6 it. The couple took a table near the back wall and on their tray there was one hamburger, one order of French fries and one drink. The little man unwrapped the hamburger and cut it 7 . Then he carefully counted out the French fries, 8 them in two piles and neatly placed one pile in front of his wife. He took a sip of the drink, his wife took a sip and then set the cup down between them. 9 the man began to eat his few 10 of hamburger the crowd began to get restless. Again you could 11 what they were thinking."That poor old couple can only 12 one meal for the two of them. A young man stood up and came over to the old couple's table. He politely 13 to buy another meal for them. The old man replied that they 14 everything. Then the crowd 15 that the little old lady 16 a bite. She just sat there 17 her husband eat. Again the young man came over and begged them 18 him buy them something to eat. They refused again. As the little old man finished eating, the young man could no longer stand it. Again he offered to buy some food. After 19 again, he asked the little old lady a question."Ma'am, why aren't you eating? You said that you shared everything. What 20 you are waiting for?" She answered,"The teeth." | ||||
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