At the ________ of his own comfort, he allowed the guest to use his bed.

单选题

Only by shouting at the top of his voice ________.

答案解析

单选题

The newly-built bullet train runs at the ________ of 300 kilometers an hour.

答案解析

单选题

This brand of wine is in short ________ at the moment, so it is very expensive.

答案解析

单选题

At the foot of the mountain .

答案解析

单选题

The rainforests ________ southward to the mouth of the river.

答案解析