“be”的用法是英语学习的基础，掌握其变化规律能帮助快速理解句子结构。以下是“be”的基本用法总结：
| 人称/数 | 肯定式 | 否定式 | 疑问式 |
| I | am | am not | Am I? |
| You | are | are not | Are you? |
| He/She/It | is | is not | Is he? |
| We | are | are not | Are we? |
| They | are | are not | Are they? |
口诀记忆：
I am, you are, he she it is，we you they are。
否定和疑问只需在动词前加“not”或调换顺序。
掌握这些，就能轻松应对一般现在时中“be”的使用。
