Ability, Admission and Advice
Basic Modals
Modals verbs modify principal verbs to express various degrees of modality such as necessity, permission, etc. . The most common modals are:
Can
Should
Can I use the commercial equipment without training?
We should invest more time to settle a debt.
Modal verbs remain in base form for all subjects.
Positive Form:
Subject + Modal + Verb + objects
Can I use the commercial equipment without training?
We should invest more time to settle a debt.
Negative Form:
Subject + Modal + Not + Verb + objects
Those raw materials can't have been good enough for your project.
You should never put up as collateral something you do not want to lose.
Question Form:
Modal + Subject + Verb + objects
Where can I find account information on Mr. Smith for last December?
Considering the value at market price, should we direct our clients to sell?
Can for Ability and Permission
'Can' is used to speak about abilities as well as asking for or giving permission.
Giving Advice with Should
Use 'Should' to ask for or give advice or suggestions.
Ought to, Had Better
'Ought to' and 'had better' express the same idea as 'should'. Although not as common as 'should' both these forms can be used in place of 'should'.
Example:
You ought to research your tax base.
We had better find a new stockbroker.
NOTE: 'had better' is a more urgent form.