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Friday, October 4, 2013

How to use COULD as an auxiliary in English?

We use this auxiliary ‘could’ in many cases. 1. In as the past equivalent of ‘can’ in complex sentence. 2. In past tense for past actions. 3. The term ‘could’ is more polite than ‘may’ which is used for making polite requests in simple present tense and future tense. 4. In simple present tense for purpose of ability or possibility. 5. In future in the past tense this ‘could’ is used.

Let us come to know about some rules of tenses where this ‘could’ be used.
1. For simple present tense in the present form of the verb the auxiliary is ‘could’.
2. For present continuous tense in the present-in-ing form of the verb the auxiliary is ‘could be’.
3. For future tense in the present form of the verb the auxiliary is ‘could’.
4. For future continous tense in the present-in-ing form of the verb the auxiliary is ‘could be’.
5. For simple past tense in the present form of the verb the auxiliary is ‘could’.
6. For future in the past tense in the past participle form of the verb the auxiliary is ‘could have’.
7. For future in the past continuous tense in the present-in-ing form of the verb the auxiliary is ‘could have been’.

Structure of sentence: as past equivalent of CAN
1. In the past equivalent of ‘can’, in complex sentences we use ‘could’ as shown below in the examples.
a. She did not solve that problem because she could not follow the steps of instructions.
b. Could you sleep for a while because it is raining heavily today?
c. Could you give me a party dress for the function which is held in the evening?

Structure of sentence: For actions in the past
1. I could not write this answer. (simple past)
2. Lakshmi could not go to office last week. (simple past)
3. The mechanic could not repair my car till yesterday. (simple past)
4. I could hear some strange voice in your room last night. (simple past)
The sentence above is also written by somebody like this ‘I heard some strange voice----‘ but when some ability is required to hear a faint voice in the past time we use ‘could’ as equal to the present tense ‘can’.
5. Could you meet the vice-principal yesterday? (simple past)

In the next lesson we would learn some more about ‘COULD’

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