I don’t go out much, mainly because I have to look after the kids.
我不大出去,主要是因为我得照看孩子们。
Increased sales during the summer were mainly due to tourism.
夏季销售额增加主要是由旅游业带动的。
We talked about various things – work, mainly.
我们谈了各种各样的事情——主要是谈工作。
adj. main
n. main、 mainstay、 mainspring