Modal verbs are combined with other verbs to express an idea or 'function' that is not expressed by the main verb alone.
These verbs include 'can', 'could', 'may' and 'might'. Here is a handy reference guide to help you with your modal verbs.
Solomon R. Guggenheim Museum Photo 2018-06-07 15:58
Solomon R. Guggenheim Museum
Fenerbahçe Photo 2018-06-07 14:49