1.Mr Obama's erratic performance is partly the result of the rollercoaster world he finds himself in.
奥巴马蹩脚的表现部分的源于他发现自己所处环境的残酷。
2.It was an erratic performance all round and not too many United players emerged with any credit.
表现很不稳定，大部分球员都没有正常发挥。
