The entry for today is a very subtle one: it’s the difference between “have to” and “need to”. There is a slight difference in nuance between them. We say “have to” when we want to talk about obligations – things we have no choice about doing. However, we say “need to” when we want to talk about things that are necessary to do in order to achieve a certain goal. For example:
I have to be at work by 9:00 a.m. every morning.
I have to help my friend move tomorrow, so I can’t have lunch with you.
You have to turn off the lights if you’re the last person to leave the office.
I want to go to Vietnam for my vacation, so I need to get a visa.
If you want to get a promotion, you need to work very hard.
If your daughter wants to be a model, she needs to lose some weight.
In the case of the second example, the person uses “have to”, even though they have a choice about helping the friend move. In these cases, when we agree to do something, we feel an obligation to do it, and so we use “have to” in these cases.
In the last three examples for “need to”, the person does the thing (get a visa, work very hard, lose some weight) in order to achieve the goal (go to Vietnam, get a promotion, be a model).
Sometimes, “have to” and “need to” can be exchanged freely in a sentence and will have a very similar meaning. For example:
I have to go to the bathroom.
I need to go to the bathroom.
I have to finish this job by Friday.
I need to finish this job by Friday.
I write down things I have to do on sticky notes.
I write down things I need to do on sticky notes.
In these cases, the meaning is very close but has a slightly different nuance. Again, when we use “have to”, we’re emphasizing the fact we have no choice; when we use “need to”, we’re emphasizing the fact that it’s necessary.