Cependant, je regrette de ne pas avoir réservé

Question

I've been told by a well-trained French teacher to never begin a sentence with "cependant." He said to use "bien que." Has this rule been superseded? Thanks!Kalpana

Cécile Janty-Davies · Accepted Answer

Bonjour Kalpana, 
Starting a sentence with 'cependant' is absolutely fine and the synonyms we give you are 'en revanche' and 'par contre', all meaning 'however', and 'on the other hand'.
Bien que would not work here as it means 'although' and 'even though' with different meanings.
Bien que nous ayons regretté de ne pas avoir apporté de guide, nous avons tout de même apprécié cette expérience sublime = Although/Even though we regretted not bringing a guide, (all the same,) we really enjoyed this wonderful experience 
Hope this helps!