1. Swimming in this river is very dangerous
->It's
2. They must tidy the school yards
-> They have
3. She intends to visit her grandma next sunday
-> She is
4. The book is interesting. I can read it twice
-> The book
5. She shouldn't stay up late
->She ought
6. She has long straight brown hair
-> Her hair
7. The water is too hot for him to drink
-> The water isn't
8. The weather is so cold that we can't go out
-> The weather
9. It's not necessary for you to stay up late
-> You don't
10. Playing with matches is very dangerous
-> It's very
11. It's dangerous to put a knife into an electrical socket
->Putting a knife
1. Swimming in this river is very dangerous
->It's very dangerous to swim in this river
2. They must tidy the school yards
-> They have to tidy the school yards
3. She intends to visit her grandma next sunday
-> She is going to visit her grandma next Sunday
4. The book is interesting. I can read it twice
-> The book is interesting enough to read it twice
5. She shouldn't stay up late
->She ought not to stay up late
6. She has long straight brown hair
-> Her hair is straight brown
7. The water is too hot for him to drink
-> The water isn't so hot that he drink
8. The weather is so cold that we can't go out
-> The weather is too cold for us can't go out
9. It's not necessary for you to stay up late
-> You don't need to stay up late
10. Playing with matches is very dangerous
-> It's very dangerous to play with matches
11. It's dangerous to put a knife into an electrical socket
->Putting a knife into an eclectrical socket is dangerous
1. Swimming in this river is very dangerous
->It's VERY DANGEROUS TO SWIM IN THIS RIVER.
2. They must tidy the school yards
-> They have TO TIDY THE SCHOOL YARDS.
3. She intends to visit her grandma next sunday
-> She is GOING TO VISIT HER GRANDMA NEXT SUNDAY.
4. The book is interesting. I can read it twice
-> The book IS SO INTERESTING THAT I HAVE READ IT TWICE.
5. She shouldn't stay up late
->She ought NOT TO STAY UP LATE.
6. She has long straight brown hair
-> Her hair IS LONG, STRAIGHT AND BROWN.
7. The water is too hot for him to drink
-> The water isn't COOL ENOUGH FOR HIM TO DRINK.
8. The weather is so cold that we can't go out
-> The weather IS NOT WARM ENOUGH FOR US TO GO OUT.
9. It's not necessary for you to stay up late
-> You don't NEED TO STAY UP LATE.
10. Playing with matches is very dangerous
-> It's very DANGEROUS TO PLAY WITH MATCHES.
11. It's dangerous to put a knife into an electrical socket
->Putting a knife INTO AN ELECTRICAL SOCKET IS DANGEROUS.