6.6.2: Review -- Must-Have to-Can-Could-Should-Had Better

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Legal Obligation $\rightarrow$ Must $\rightarrow$ You must wear a seatbelt when driving.

Reporting a rule/obligation $\rightarrow$ Be supposed to $\rightarrow$ You’re not supposed to smoke here.

A person of authority stating a need $\rightarrow$ Must $\rightarrow$ Mother to child: ‘You must do your homework before dinner.’

Personal need / obligation $\rightarrow$ Have to $\rightarrow$ I have to do my homework.

I have to call my mother.

$\rightarrow$ Have got to $\rightarrow$ I’ve got to call my mother.

Ability $\rightarrow$ Can $\rightarrow$ I can run 2 miles.

I am able to run 2 miles.

Possibility $\rightarrow$ Can $\rightarrow$ I can meet you at 5pm.

It is possible for me to meet you at 5pm. I have time then.

I can afford to pay $800 a month for rent.

It is possible for me to pay $800 a month for rent.

Permission $\rightarrow$ Can $\rightarrow$ I can stay out until midnight.

I am permitted to stay out until midnight.

I am allowed to stay out until midnight.

$\rightarrow$ May $\rightarrow$ I may stay out until midnight.

Past Ability $\rightarrow$ Could $\rightarrow$ In my country, I could easily communicate with everyone.

In my country, I was able to easily communicate with everyone.

Past Permission $\rightarrow$ Could $\rightarrow$ As a child, I couldn’t stay up after 10pm.

As a child, I wasn’t able to stay up after 10 pm.

Advice $\rightarrow$ Should $\rightarrow$ You should always get a good night’s sleep before taking a test.

You shouldn’t go to that movie. It wasn’t very good.

Warning $\rightarrow$ had better $\rightarrow$ You’d better pay your rent on time.

You’d better not come to class late again.

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