Could I write this as "Nous aimons qu'il a une femme."? If so, how can I tell the difference between the two verb tenses if the translation to English is the same?
The subjonctive is compulsory here.
more details here: http://french.about.com/od/grammar/ss/subjunctive.htm
Is 'We like him to have a wife.' correct, please? I mean, can we say for sure if he already has a wife, or they just like him to get married?
if the guy is currently single, you would probably say something like: we wish he had a wife or we'd like him to have a wife.
in French: nous aimerions (conditional) qu'il ait une femme