Can vs Should
Can and Should are two auxiliary verbs used in the English language with difference. Normally they are two verbs that are confused by the user. The auxiliary verb ‘can’ is used to indicate the idea of ‘capability’. On the other hand, the verb ‘should’ is used in the imperative. This is the main difference between the two words.
The auxiliary verb ‘can’ is used in questions, whereas the auxiliary verb ‘should’ cannot be used in questions as in the examples,
1. Can I have your pen for a moment?
2. Can you come home tomorrow?
In both the sentences, you can see that the verb ‘can’ is used in the formation of question. At the same time you cannot use the auxiliary verb ‘should’ in its place. To ask ‘should I have your pen for a moment?’ is wrong in usage.
On the other hand, ‘should’ is used in sentences to indicate an ‘order’ or ‘direction’ as in the examples,
1. You should make it possible somehow or other.
2. Francis should get it by tomorrow.
In both the sentences mentioned above, the word ‘should’ is used indicating an order or a direction. The auxiliary verb ‘should’ is sometimes used in the beginning of a sentence in the peculiar sense of ‘if’ as in the sentences,
1. Should I get up very early in the morning, I can easily complete the entire work by noon.
2. Should he come in the evening, I would discuss the matter with him.
In both the sentences, the verb ‘should’ is used in the peculiar sense of ‘if’ and hence, the meaning of the first sentence would be ‘if I get up very early in the morning, I can easily complete the entire work by noon’, and the meaning of the second sentence would be ‘if he comes in the evening, I would discuss the matter with him’.
Sometimes, the auxiliary verb ‘can’ is used indicative of permission or request as in the sentences,
1. Can I speak to you now?
2. Can you give me your phone number?
In both the sentences, the verb ‘can’ is used indicative of request or permission. This is an important observation to make in the usage of the auxiliary verb ‘can’. The past tense form of ‘can’ is ‘could’. These are the main differences between the two words that are often confused, namely, can and should.