The word ‘can’, in its most common form, means to be able to do something. In most cases, it can be replaced with a form of ‘be able to’.
“I can sing. ”
The above sentence means that the person has the ability to sing, not necessarily that they are singing at the moment.
It is also used to ask permission in informal situations.
“Can I have some more cookies? ”
In formal situations, it is better to use the more formal phrasing of ‘may’.
“May I have some more cookies? ”
‘Can’ in this form, is an auxiliary verb, which means that it is used with another verb to show that the person is able to perform the action.
There are a few other meanings of the word. It can also mean a sort of container. They are usually cylindrical and made of metal, but it can also refer to plastics and oddly shaped containers, such as watering cans. The word ‘can’ is also a verb which means to put something in a container, to stop something, or to fire someone from a job.
The word ‘could’ means the same as the auxiliary form of the word ‘can’: the ability to do something. However, it is the past tense form of the word.
“I can sing. ”
“I could sing, but I have since lost my voice. ”
Aside from that, it serves as a few different forms as a conditional word, also known as a modal verb. This means that it is a form of a word used when there is a condition involved, meaning that it is used when whether it can happen depends on something else happening.
“I can sing, or I could if I wanted to. ”
One example is the subjunctive mood, which refers to something that is not currently true. For example, a hope, a wish, or an alternative version of events, are all considered to be subjunctive.
“If I could fly, I could get the cat out of the tree with no problem. ”
“I wish I could have a million dollars. ”
“If we’d taken the other route, we could
have been trapped in traffic for five hours. ”
This is fairly unusual in English. The subjunctive mood is not often a separate form of a word, as it is in many other languages, such as the Romantic languages. More often, it is set off by different phrases such as ‘If I were’.
‘Could’ is also used to suggest or ask that someone do something.
“Could you please shut the window? ”
When it is used this way, it can be used in exactly the same way as the word ‘can’.
“Can you please shut the window? ”
However, the word ‘could’ is considered to be slightly more polite than using the word ‘can’. Because ‘could’ depends on conditions, it depends on the condition of the person agreeing to do it. ‘Can’, on the other hand, assumes that the person is willing to do it, which is not always the case.
To summarize, ‘can’ is the present tense version of the word and ‘could’ is the past tense version of the word. ‘Could’ is also used when a condition must be fulfilled in order for the thing to happen. ‘Can’ is used when there is nothing that would stop the thing from happening. When asking someone to do something, either word can be used, but ‘could’ is considered to be more polite.
