In this lesson, you can learn how to use the English modal verbs 'can' and 'could' to talk about ability. You will also learn about the verbs 'be able to and 'managed to' to talk about ability. These verbs are not modal verbs, but we cannot use the modal verbs 'can' or 'could' in every situation to talk about ability, so sometimes we need to use a different verb. In this video, you will see: 1) How to use 'can' to talk about abilities in the present or future 2) How to use 'could' to talk about abilities in the past 3) When you need to use the verbs 'be able to' or 'managed to' 4) The difference between 'can' or 'could', and 'be able to' 5) The two different meanings of 'could' 'Can' and 'could' are used to talk about abilities in the past, present or future. Sometimes, there isn't a form of 'can', and we need to use the verb 'be able to'. For example, 'can' doesn't have a present perfect form, so if you want to use 'can' in the present perfect, you need to use 'be able to'. In other forms, 'can' or 'could' and 'be able to' generally have the same meaning. However, if you are talking about abilities in the past, 'could' and 'be able to' are sometimes different. We use 'could' to talk about general abilities in the past, while if you want to talk about a specific ability at a specific time, you need to use 'be able to'.
Since the word contract means to squeeze together so the word contraction means to shorten two words together by placing apostrophe or by omitting some letters. Informal contractions are short forms of other words that people use when speaking casually. They are not exactly slang, but they are a little like slang.
Please remember that these are informal contractions. That means that we do not use them in "correct" speech, and we almost never use them in writing.
Also note that, unlike normal contractions, we do not usually use apostrophes (') with informal contractions when written.
In this video, Grammar Squirrel and her friends consider the differences between using the active and passive voice when writing. She learns that using the active voice is generally preferable, and finds out why it normally leads to shorter, more succinct sentences. She also learns that the passive voice is useful in some situations, and considers some of these.
Present Simple grammar explanation from Cambridge University Press.
Most English learners strongly associate future with WILL, but here is news, WILL is not the most common way to talk about the future. On this video we will see the general difference between WILL and GOING TO (= GONNA).