根据句意及汉语提示，在下列句中空缺处写出单词的正确形式

He came to ________ (苏醒) at last.

根据句意及汉语提示，在下列句中空缺处写出单词的正确形式

Why is the street so ________(拥挤)?

在空缺处填入所缺的冠词，不需要处打×

The book is both ________ unusual present and ________ useful tool.

在空缺处填入所缺的冠词，不需要处打×

________ bridge over ________ river was built many years ago.

在空缺处填入所缺的冠词，不需要处打×

________ earth moves round ________ sun.

在空缺处填入所缺的冠词，不需要处打×

On ________ Teachers' Day, we send our best wishes to the teachers.

在空缺处填入所缺的冠词，不需要处打×

He sits in ________ front of the classroom to see clearly.

在空缺处填入所缺的冠词，不需要处打×

I'm going to be a scientist in ________ future.

在空缺处填入所缺的冠词，不需要处打×

She is a popular dancer and ________ singer.

在空缺处填入所缺的冠词，不需要处打×

He left for Shanghai by ________ train.