Mother-in-law (장모님을 영어로?)

장모님을 영어로?
Mother-in-law. (*Should be capitalized)

장인어른을 영어로?
Father-in-law.

시누이를 영어로? 
Daughter-in-law.

I didn't know that here also has a problem between mother in law and wife. 

That was interesting. 

I saw this articles. Like How to deal with Mother in law. and 10 things never to say to your Mother-in-law.

http://www.womansday.com/relationships/family-friends/g1119/how-to-deal-with-mother-in-law/?slide=1