modal verbs ( defective verbs ) ( can , could , may , might , shall , should , will , would , must , ought to ) Barbara will eat the cake You ought to send the package by registered mail They cannot hold the metting in that room Will many people attend the lecture ? You must do it right now NObody can measure the depth of this river People can't take reference books home We ought not to speak such things in public How much will they pay you ? They shouldn't build the resort on such a beautiful beach We ought to clarify the problem of environment pollutiion They may organize a new group last week