The deer crossed over to the other side of the river.那只鹿过到河对岸去了。

The bridge crosses over the river.那座桥横跨在河上。

People were crossing over to vote for the other party's candidate. [=people in one political party were voting for the other party's candidate]人们开始转变立场，改投另一政党候选人的票。

The singer crossed over from country to pop. [=the singer changed his style of music from country to pop]那位歌手转变了音乐风格，从乡村音乐改为通俗音乐。