Verbs Forms Worksheet Based On Class 9 English Workbook Unit 1

Complete the following passage by choosing the correct word from the given options.

Scientists think they …………1………. (figure / figured / have figured) out the real job of the seemingly useless appendix: it …………2………….. (produced / is producing / produces) and protects good germs for your gut. For generations, appendix …………3…………….. (is dismissed / has dismissed / has been dismissed) as superfluous. Doctors …………4………….. (thought / have thought / had thought) it had no function, surgeons …………5…………. (remove / have removed / removed) it routinely and people …………6………… (lived / have lived / are living) fine without it. However, the new study …………7………….. (suggested / suggest / suggests) that appendix is responsible for the massive amount of benign bacteria ……………8…………. (present / presented / have presented) in the human digestive system.

Answers

Scientists think they have figured out the real job of the seemingly useless appendix: it produces and protects good germs for your gut. For generations, appendix has been dismissed as superfluous. Doctors thought it had no function, surgeons removed it routinely and people lived fine without it. However, the new study suggests that appendix is responsible for the massive amount of benign bacteria present in the human digestive system.

Notes

Use the simple present to talk about facts, general truths etc.

Use the present perfect to talk finished events when there is no time reference.