Tim, don’t touch the box. There is       in it.

A．nothing dangerous                      B．something dangerous

C．dangerous something                    D．dangerous nothing

根据句意，写出括号内所给单词的适当形式。

1.Many of my friends were invited to the party last Sunday because of my _________ ( twenty ) birthday. 

2.Boys, don’t touch the machines, or you may hurt _________ ( you ). 

3.The International Union Against Cancer says about seven hundred million children _________ ( breath ) smoke-filled air. 

4.I can’t understand his             (silent) on such an important matter.

Boys, don’t touch the machine, or you may hurt _________.

A．yourself          B．themselves        C．himself           D．yourselves

Tim, don’t touch the box. There is       in it.

Boys, don’t touch the machine, or you may hurt _________.