verb

should

Used to express advice, duty, or an expected result.

You should wear a helmet when you ride your bike.

Etymology

Should developed from the past form of shall. Its older obligation sense broadened to advice and to outcomes considered reasonably expected.

More examples

  • We should keep the promises we make.
  • The package should arrive by Friday.
  • You should have asked before borrowing my car.

Forms

should

Similar words

ought
Usually takes “to” and expresses similar advice, duty, or expectation.
must
Expresses a stronger obligation rather than advice or mild expectation.