Ex.11.употребляйте слово "can" в правильной форме с последующим соответствующим инфинитивом. 1.you (to call) a little later? I'm afraid I shall be busy till seven. 
 2. ___ it (to be) a joke? I felt very much offended.
 3. You not (to see) him at the meeting. He said he had been ill at that time. 
 4.___ we (to cover) fifteen kilometers? The village is not yet seen. 
 5. Henot (to forget) your address; he has visited you several times. 
 6. If you had let us know, we(to send) our car for you. 
 7. I should be very much obliged to you if you ___ (to lend) me your dictionary for a couple of days. 
 8. I don't believe her, she(to fail) to recognize me. 
 9. He said he(to manage) the task by himself. 
 10. Why didn't you ask me? I(to do) it for you.