Which is the correct translation for "I went to the bathroom twice": 去了厕所两次 or 去厕所两次了?
The verb particle '了' after '去' in &quot;去了厕所两次&quot; indicates the verb '去' is completed, so &quot;去了(went to) 厕所两次 (the bathroom twice)&quot;  is the correct translation
The final particle '了' after '去厕所两次'  emphasizes 两次 --&gt; &quot;两次了&quot; = &quot;twice already&quot;
But '了' here can also function as a verb particle that indicates the verb phrase 去厕所两次 as a completed action --&gt; &quot;[去]厕所两次[了]&quot; = &quot;[went to] the bathroom twice&quot;
Both translations are valid, but the first one is more literal (word for word translation)