1 . When you combine enough steps, we will make ________ to the finishing line(用适当的词填空)

2 . ________ is very likely that she will ring me tonight. (用适当的词填空)

3 . Is________ necessary for us to take notes during class? (用适当的词填空)

4 . ________ took the police only several days to crack the case. （用适当的词填空）

5 . ________ was interesting to be in a different environment. （用适当的词填空）

6 . ______ is unfit to drink the water in this well. (用适当的词填空)

7 . _______ soon became apparent to everyone that he couldn’t sing. (用适当的词填空)

8 . ________ is a good idea to take part in social activities, which can promote our understanding of the world. （用适当的词填空）

9 . ________ makes me sad to hear that you can’t get used to the life in the new school. （用适当的词填空）

10 . Johnson’s father who is a firefighter owes ________to the doctor that he is still alive. （用适当的词填空）