Layered modal meanings

Interpret combinations of modality, aspect and voice that encode probability, obligation, expectation or counterfactuality.

When do we use it?

Build complex modal phrases while preserving the intended time and voice.

Form

After a modal, add have for prior time, be for progressive or passive meaning, and combine them in fixed order.

• may have been overlooked
• should be being monitored
• could have been working

Key contrast

At C2, grammar is a resource for controlling perspective, density, rhythm and register, not merely avoiding error.

Common mistakes

• may been overlooked → may have been overlooked
• should being monitored → should be being monitored

Remember

Interpret combinations of modality, aspect and voice that encode probability, obligation, expectation or counterfactuality.

Quick check

• Identify the information focus and logical relationship.
• Check auxiliary order, reference and complement pattern.
• Choose the option that is idiomatic in the intended register.