一、Reading
Jack seldom gets together with his friends. He usually stays at home with his pet dog, Lucky. They sometimes go for long walks in the park. Although Jack is often alone, he is never lonely. He always tells his friends that a dog is man's best friend.
二、解析
■ Jack seldom gets together with his friends.
- 主：Jack
- 状：seldom, 频率副词。
- 系：gets，相当于 is.
- 表：together with his friends.
- 复合介词：together with
- 宾：his friends.
■ He usually stays at home with his pet dog, Lucky.
- 主：He
- 状：usually
- 谓：stays
- 地状：at home
- 伴随状语：with his pet dog
stay：vi. 待在，停留在
■ They sometimes go for long walks in the park.
- 主：They
- 状：sometimes
- 谓：go
- 目状：for long walks
- 地状：in the park.
■ Although Jack is often alone, he is never lonely.
- 让步状从：Although Jack is often alone
- 引导词：Although
- 主：Jack
- 系：is
- 状：often
- 表：alone
- 主：he
- 系：is
- 状：never
- 表：lonely
■ He always tells his friends that a dog is man's best friend.
- 主：He
- 状：always
- 谓：tells
- 直宾：his friends
- 间宾从句：that a dog is man's best friend.
- 主：a dog
- 系：is
- 定：man's best
- 表：friend.
三、频率副词的位置
常见的频率副词：seldom（很少）、usually（通常）、often（经常）、sometimes（有时候）、never（从不）、always（始终）。频率副词通常使用在一般现在时中。
在句中的位置：
- 句中有 be 动词时，频率副词置于该 be 动词之后。
- 句中有一般动词时，频率副词置于该动词之前。
