to spend time visiting a lot of websites

He spends a lot of time surfing the internet/Net/Web. 他花很多时间上网。

to ride on a wave as it comes towards land, while standing or lying on a special board

They go surfing every weekend. 他们每个周末都去冲浪。

the tops of the waves on the sea when they are near to the coast or hit against rocks

We were almost deafened by the crash/roar of the surf. 拍岸的涛声震耳欲聋。