It is certain that they will support our decision. (Simple)

• Complex sentence এ it is certain, it is surely, it is sudden থাকলে Simple sentence এ- it is certain এর পরিবর্তে certainly হবে + এর পরের relative pronoun টি বাদ যাবে + বাকি sentence টি বসবে।Complex: It is certain that they will support our decision.Simple: Certainly, they will support our decision.• অন্য দিকে, - it is certain এর পরিবর্তে certainly হবে,- it is sudden এর পরিবর্তে suddenly হবে,- it is surely এর পরিবর্তে surelyহবে।যেমন:Complex: It is certain that he will come here.Simple: Certainly, he will come here.Complex: It was sudden that he lost his mobile.Simple: Suddenly, he lost his mobile.Complex: It is sure that Riva has done it.Simple: Surely, Riva has done it.Source: Advance Learner's English Grammar and Composition by Chowdhury & Hossain.