It's partly my fault.

这在一定程度上是我的错。

He let out a long sigh, mainly of relief, partly of sadness.

他长叹一口气，主要是因为如释重负，也有一部分是因为伤心。

I have not worried so much this year, partly because I have had other things to think about.

今年我不太担心，在某种程度上是因为我有别的事情要考虑。

I feel partly responsible for the problems we're in.

我觉得应为我们遭遇的问题负部分责任。