Ch 1

Modals — Obligation and Advice

Should, ought to, had better for giving and receiving advice.

need to, needn't, don't have to, should
B1 Pre-intermediate

Modals: Obligation and Advice

need to, needn't, don't have to, should
need to
Important but not a law - personal necessity
have to
Rule or law - external obligation
don't have to / needn't
No obligation - not necessary
should / shouldn't
Advice - right or wrong thing to do

No obligation - three ways

I don't have to work on Sundays.
Not required - but I can if I want.
You needn't pay for your food.
Not necessary - I am paying.
You don't need to bring anything.
Same meaning - slightly more informal.
Don't have to, needn't and don't need to all mean it is NOT necessary, but it is allowed.

Need to vs Have to

need to - personal importance
You need to be careful with your passport.Important but ultimately your choice.
have to - rule or law
You have to show your passport at the airport.Legal requirement - no choice.

Common mistakes

Where learners go wrong most often

You should to study more.
You should study more.
No 'to' after modal verbs
You don't should do that.
You shouldn't do that.
Don't + modal is wrong: use modal + n't
He needs study harder.
He needs to study harder.
"Need to" requires to; modal "need" does not

Summary

need to / have to
Necessary - something that must be done
don't have to / needn't
Not necessary - no obligation
should / shouldn't
Advice - the right or wrong thing to do
Practice now →
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