IN

In主要在下面这些名词后面：

* a rise in something
例句: There has been a rise in prices recently.
最近价格上涨了。

* an increase in something
例句: We have seen many increases in production levels.
我们看到生产水平有了很大提高。

* a fall in something
例句: There has been a fall in prices recently.
最近价格有了下降。

* a decrease in something
例句: We have seen many decreases in production levels.
我们看到生产水平有了很大下降。