How to form and when to use the verb to BE in present tense?

视频信息

答案文本 复制

视频字幕 复制

Welcome to our lesson on the verb 'to be' in present tense. The verb 'to be' is the most fundamental and important verb in English. It helps us describe states of being, identity, and characteristics. For example, we say 'I am happy' to describe how we feel, 'She is a teacher' to identify someone's profession, and 'They are students' to describe what people do. Let's explore how to form and use this essential verb. Now let's learn the three forms of the verb 'to be' in present tense. There are exactly three forms: AM, IS, and ARE. Each form goes with specific subjects. AM is used only with the pronoun 'I'. IS is used with singular third person subjects like 'he', 'she', and 'it'. ARE is used with 'you', 'we', and 'they'. Here's a helpful memory tip: 'I am always with AM', 'IS goes with singular third person', and 'ARE for everything else'. This pattern will help you choose the correct form every time. Now let's practice forming positive statements with the verb 'to be'. The structure is simple: Subject plus BE plus Complement. The complement can be an adjective like 'happy' or 'tall', a noun like 'student' or 'teacher', or a prepositional phrase like 'at home'. Let's look at examples with each form. 'I am a student' uses AM with the subject I. 'You are kind' uses ARE. 'He is tall' and 'She is busy' both use IS with singular third person subjects. 'It is cold' also uses IS. 'We are friends' and 'They are happy' both use ARE with plural subjects. Notice how the BE verb changes based on the subject, but the structure remains the same. Now let's learn how to form negative statements with the verb 'to be'. To make a sentence negative, simply add 'NOT' after the BE verb. The structure becomes: Subject plus BE plus NOT plus Complement. Let's see some examples. 'I am tired' becomes 'I am not tired'. Notice how we add 'not' after 'am'. 'She is ready' becomes 'She is not ready', and we can contract this to 'She isn't ready'. 'They are here' becomes 'They are not here', which can be contracted to 'They aren't here'. Remember that 'am not' cannot be contracted to 'amn't' - this form doesn't exist in English. Both full forms and contractions are commonly used in everyday English. Now let's learn how to form questions with the verb 'to be'. To create yes/no questions, we invert the subject and the BE verb. For example, 'You are happy' becomes 'Are you happy?' Notice how 'are' moves to the beginning. 'He is coming' becomes 'Is he coming?' and 'They are ready' becomes 'Are they ready?' The structure is: BE plus Subject plus Complement plus question mark. We can also ask 'Am I late?' with the first person. For short answers, we use the same BE verb: 'Yes, I am' or 'No, I'm not', 'Yes, he is' or 'No, he isn't', 'Yes, we are' or 'No, we aren't'. This inversion pattern is consistent for all forms of the verb 'to be'.