The phrase ‘Be able to’ can be used in place of ‘Can’
Usage of ‘Can’ instead of ‘Be able to’
- He can make toys with soil – He is able to make toys with soil.
- I am unable to figure this out – I can’t figure this out.
- They were able to catch the killer – They could catch the killer.
‘is/am/are to’ instead of ‘will or shall’
The structure is/am/are+ to can be used to express simple futurity.
- He is to leave tomorrow – He will leave tomorrow.
- The prime minister is to visit America next year – The Prime Minister will visit America next year.
- They are to get information from rats – They will get information from rats.
‘is/am/are + to’ instead of ‘must’
The structure ‘is/am/are + to’is also used to give commands. Therefore, it can be used in place of must.
- I am to write a blog in an hour – I must write a blog in an hour.
- He is not to wait for more than an hour – He must not wait for more than an hour.
Had better instead of should or ought to
- You had better asked him – You should ask
Had better may also express a threat.
- He had better be wary.
Have to instead of must
- I have to finish food – I must finish food.