I am simply trying to ascertain the facts of the case. 我只是想查清这件案子的事实真相。

+whether/what/how etc We need to ascertain whether the project is feasible. 我们需要弄清楚这项计划是否可行。

+that The police have ascertained that he knew the victim. 警察已查明他认识受害者。

+from This much could easily be ascertained from the newspapers. 这么多都能轻易地从报纸上查到。

ascertain the cause/nature/extent of sth Experts were unable to ascertain the cause of the accident. 专家们无法查出事故原因。