1.     The weather is so bad that we can’t go out. (too)

->The weather is too bad for us to go out.

2.     The film was so boring that we couldn’t go on seeing it. (too)

->The film was too boring for us to go on seeing.

3.     You speak so fast that I can’t catch up with your words. (too)

->You speak too fast for me to catch up with your words.

4.     He studied so badly that he couldn’t pass the exam. (too)

->  He studied too badly to pass the exam.

5.     My sister is so weak. she can’t run. (too)

-> My sister is too weak to run.

6.     The coffee was very hot. They couldn’t drink it. (too)

->The coffee was too hot for them to drink.

7.     This table is not big enough for 10 people to sit. (too)

->This table is too small for 10 people to sit.

8.     The water is warm enough for you to have a bath. (too)

->The water isn't too cold for you to have a bath.

9.     My parents allowed me to go sightseeing. (let)

->My parents let me go sightseeing. 

10.  The CEO let me use his car for private purposes. (to use)

->The CEO allowed me to use his car for private purposes.