English Grammar Step G4 (new)

"Could" is the past tense of "can" and is used to describe past abilities or possibilities. For example: "She could speak three languages."

"Be able to" is used when "can" or "could" are not grammatically possible, often in different tenses or when expressing specific situations. For example: "I will be able to help you tomorrow."

"Must" is used for strong obligations or logical conclusions, often from the speaker’s perspective, while "have to" is used for external obligations. For example: "I must finish this work" vs. "I have to finish this work by tomorrow."

"Might" and "may" are used to express possibility in the present or future. They are often interchangeable, but "might" can indicate a slightly lower probability. For example: "It may rain tomorrow" or "It might rain tomorrow."

"Must" in the present tense is used to express a strong obligation or a logical conclusion. For example: "You must wear a seatbelt" or "She must be at work."

"Could have" is used to express that something was possible in the past, but didn’t happen. For example: "You could have called me."

The structure is: subject + must + have + past participle. For example: "She must have left the house early."

"Can't have" or "couldn't have" are used to express that something was not possible in the past. For example: "He can't have forgotten the meeting" or "They couldn't have seen us."

"May" and "might" can be used to indicate that an action is possible in the future. For example: "I might go to the park later" or "She may come to the party."

"We could visit the museum tomorrow."

"Must" does not have a past form, so "had to" is used to express past obligations. For example: "I had to leave early yesterday."

To form questions, we place "can" or "could" before the subject. For example: "Can you help me?" or "Could you pass the salt?"

"Can" is more commonly used to talk about general abilities, while "be able to" is used when "can" is not possible due to tense or grammatical constraints. For example: "She can swim" vs. "She has been able to swim since she was a child."

"Could" is preferred over "can" when talking about hypothetical or polite requests, as well as in conditional sentences. For example: "Could you help me?" or "If I had time, I could visit you."

"May have" and "might have" are used to express possibilities in the past. They are often interchangeable, but "might have" can suggest a slightly lower probability. For example: "She may have missed the train" or "He might have forgotten the keys."

"Must" is used to make logical conclusions based on evidence. For example: "You must be tired after such a long journey."

"I might go to the gym later."

"Can't" or "cannot" are used to express impossibility in the present. For example: "That can't be true."

"Might as well" is used to suggest that something is a good idea because there is no better alternative. For example: "We might as well leave now."