泰坦尼克号为什么沉没了?
Why did the Titanic sink?
第一,如果它没有出海那么就不会沉没；
First of all,it wouldn't have sank in ocean if it remained unsailing.
第二,如果它保持警惕,也不会沉没；
Secondly,if people in Titanic were highly aware of danger,it wouldn't sink.
第三,船长如果对信息足够重视……
And the third is,if the captain took respect of the info.
综上,它必然会沉没
Therefore,the Titanic sank,for sure.
用了几个verbal expression(日常表达）
请参考~