1.People think the earth is flat.(passive)
-> The earth is thought to be flat
2.we don't go to school late any more(used to)
-> We uesd to go to school late
3.I can't go climbing and hiking this weweekend. (I wish )
->…I wish i could go climbing and hiking this weekend
4.Nam will have a cold if he doesn't wear warm clothes in winter.(unless)
->……unless Nam wears warm clothes in winter, he will have a cold