1.   1. can't be   2. had to leave   3. was to
4. have snowed   5. had to attend   6. should have helped                                           7. must he still be waiting for us?   8. ought to have come/were to come                      9. must have been waiting   10. don't have to come   11. should have disconnect
12. has to go   13. couldn't; was to go   14. needn't have told                                             2.   1. He couldn't have read this book.   2. He shouldn't have come, everything had been already done.   3. You shouldn't have spoken to her in English.                          4. If the weather is fine we might go to the country.   5. He couldn't have forgotten to come.   6. You may not rewrite the composition   7. You shouldn't have gone there yesterday.