练习材料：Lesson 10 Not for jazz
We have an old musical instrument. It is called a clavichord. It was made in Germany in 1681.Our clavichord is kept in the living room. It has belonged to our family for a long time. The instrument was bought by my grandfather many years ago. Recently it was damaged by a visitor. She tried to play jazz on it! She struck the keys too hard and two of the strings were broken. My father was shocked. Now we are not allowed to touch it. It is being repaired by a friend of my father's.
任务配置：L0+L4
知识笔记：
instrument/ˈɪnstrəmənt/乐器
clavichord/ˈklævɪkɔ:rd/击弦古钢琴
strike - struck - struck
string（乐器的）弦
一、动词的过去式是一个动词，单独作谓语。不能与助动词、情态动词连用。它的词性与动词的第三人称单数一样。 动词的过去式可分为规则动词和不规则动词。规则动词的过去式变化如下：
1、一般情况下，动词词尾加 -ed ，如：
worked played wanted acted
2、以不发音的 -e 结尾动词，动词词尾加 -d，如：
lived moved decided declined hoped judged raised wiped
3、以辅音字母 + y结尾的动词，把-y变为-i 再加-ed，如：
studied tried copied justified cried carried embodied emptied
4、以一个辅音字母结尾的重读闭音节动词，双写词尾辅音字母，再加 -ed，如：
stopped begged fretted dragged dropped planned dotted dripped
5、不规则动词的过去式变化规律性不强，须多加记忆。
go - went，make - made， get - got ，buy - bought ，come - came ，fly-flew ，is/am-was， are-were ，see-saw ，bring-brought，do-did，teach-taught, think-thought, are-were, say-said,sit-sat.
二、动词的过去分词是动词的一种非谓语形式，也叫非限定性动词。不能独立作谓语，只能与助动词一起构成谓语。如:“have/has/had +过去分词”构成完成时态;“be+过去分词”构成被动语态等。它相当于一个形容词或副词，在句中起一个形容词或副词的作用，可作表语、定语、补语等。它的作用与现在分词doing类似。过去分词表的意义是被动或完成。
三、不过，过去式和过去分词最主要的区别是:过去式是一个动词，而过去分词是一个动词的非谓语形式，相当于一个形容词或副词。
练习感悟：有点开始出现拖延症的倾向了，坚持住
