从下面方框中选出恰当的词或短语放入短文相应的空格处，使短文语句通顺意思完整。其中有两项是多余的，将所选词的代号写在题后对应横线上。

Thomas Edison lived in America. He invented plenty of electrical appliances (电器)and   1   people know him.

At that time there was no electric lamp (电灯) in the world. And it brought people   2  . Young Edison decided to   3   it. He didn’t know which material was suited to be a lamp filament (灯丝). He   4   many times and he spent a lot of time on it. Some friends of his asked him to   5   the experiments but he didn’t listen to them and tried his best to find the   6  .

One afternoon a friend of his came to visit him. He was doing his experiment in the lab   7   the man came in. But he only asked his friend to   8   and didn’t stop to talk with him. The man sat for a long time and Edison said nothing to him. He was   9   Edison and said. “You’ve done the experiments 1,200 times but you’ve failed 1,200 times.” “You’re right, my friend,” Edison went on doing his experiments and said, “But I have known that 1,200 materials   10  to be a lamp filament.”

1．           2．          3．           4．           5．          

6．           7．          8．           9．           10．