When you use other tenses you have to replace them. Printable and online modal auxiliaries exercise with answers for teachers and students- Could / had to / must / can / may.
Must - Mustnt exercises PDF Practise modal verbs of obligation. You can only use them with the present tense. Modal mix exercise 1: multiple choice exercises practising various modals exercise 2. Modal verbs don't have a past form (except can) and a past participle (3 rd form). The most common modal verbs are can, may and must. We also use them to make requests and offers.
Can - Be able to worksheets Can compared with be able.