Choose the right form. if i (1. didn't bother/ hadn't bothered) him with our problems so much last year he (2. would supply/ would have supplied) us with the required equipment. if we (3. didn't buy/ hadn't bought) a laptop for john, he (4. wouldn't be able, wouldn't have been able) to use the e-mail now. if the television (5. was not invented, hadn't been invented) in the 19th century, it (6. would be invented/ would have been invented) in the 20th. if james (7. had named/ named) some great discoveries in the history of human civilization, he (8. would get/ would have got) a good mark but his mark was poor. but for isaac newton the mankind (9. wouldn't know/ wouldn't have known) the law of universal gravity. i know your parents are very unhappy. if i (10. were/ had been) you, i (11. wouldn't be/ wouldn't have been) so indifferent to their problems. if they (12. had/ had had) various approaches to the problem, they (13. would tell/ would have told) us about them. let s ask them about it. i wish we (14. could/ had been able to) always predict the near future. if paul (15. were not/ hadn't been) a surgeon, he (16. would be/ would have been) in scientist now. if he (17. were not interested/ hadn't been interested) in science and technology, he (18. wouldn't enter/ wouldn't have entered) the science department of manchester university. but he is among the best students.
