下列各句加横线的词，为词类活用的一项是（ ）

Whatever you do, we are always ________ your side

下列各句中，没有语病的一句是

It was in Beihai Park _____ they made a date for the first time ______ the old couple told us their love story.

I came here by taxi and the driver _____ me 50 yuan. — Really? You _____ by bus.[ ]