在英语中，时态是英语语法中的难点之一，它种类多，容易混淆，下面结合前面学过的九大句型通过例句说明，并做时态比较，帮助英语学习者理解和掌握时态的用法。

    一．何谓时、体、态

    所谓时是指动作或状态所处的时间。分为过去、现在和将来。以下以我们前面讲过的十大简单句型为主线，系统讲解。进而对此有更深的理解。例：

    1．主语+系动词+表语

    1）. Tom is a college student.
    Tom was a college student.
    Tom will be a college student.

    2 ）It is sunny today.
    It was sunny yesterday.
    It will be sunny tomorrow.

    2. S +V+O 主语+谓语+宾语
    Tom studies English now.
    Tom studied English years ago.
    Tom will study English.

    3. S+V 主语+谓语
    Tom studies hard.
    Tom studied hard before.
    Tom will study hard in the future.

    4. S+V+Oi+Od 主语+谓语+间接宾语+ 直接宾语
    Tom gives me a book.
    Tom gave me a book.
    Tom will give me a book.

    5. S+V+O+S 主语+谓语（动词）+宾语+补语
    Tom makes me sad.
    Tom made me sad.
    Tom will make me sad.

    6. S+have+O 主语 +have+ 宾语
    Tom has many friends.
    Tom had many friends.
    Tom will have many friends.

    7. “there + be …”句型
    There are some books on the shelf.
    There were some books on the shelf.
    There will be some books on the shelf.

    8. 比较句型

   1) A …than + B （比较级）
   Tom is taller than sally.
   Tom was taller than sally.
   Tom will be taller than sally.
   Tom works harder than sally.
   Tom worked hard than sally.
   Tom will work hader than sally.

   2) as…as… （原级比较）
   Tom is as tall as sally.
   Tom was as tall as sally.
   Tom will be as tall as sally.
   Tom works as hard as sally.
   Tom worked as hard as sally.
   Tom will work as hard as sally.

    9． “It is + adj形容词 + to do /从句”
    It is important to learn English grammar.
    It was important to learn Russin grammar.
    It will be important to learn Russin grammar.
    It is important that we learn English.
    It was important that we learnt Russin grammar.
    It will be important that we learn Russin grammar