经过若干次试验，他们终于成功了。

Jīngguò ruògān cì shìyàn, tāmen zhōngyú chénggōng le.

After several experiments, they finally succeeded.

我们已经解决了若干技术问题。

Wǒmen yǐjīng jiějué le ruògān jìshù wèntí.

We have already resolved several technical problems.

会议上讨论了若干与环保相关的问题。

Huìyì shàng tǎolùn le ruògān yǔ huánbǎo xiāngguān de wèntí.

At the meeting, several environmental protection–related issues were discussed.