反义词是in，意思是里边，例如：

1、We were locked in.我们被锁在里面了。

2、It startled me to find her sitting in my office.我一进办公室，发现她坐在里面，把我吓了一跳。

3、Our cars get blocked in and we can't leave for ages.我们的车被堵在里面，要等很久才能走。