But to prevent the confusion and misunderstanding which might arise in changing the form of a proper noun, we do not change its form in writing the plurals; for example:

It would be confusing to say eight Henries, the two Maries.

The title is made plural when several are referred to, thus:

Mr. HayesThe Messrs. Hayes
Miss SmithThe Misses Smith

78. The title is made plural when used with several names, thus:

79. In the case of nouns formed of two or more words, when the compound word is so familiar that the parts are not thought of separately the s is added to the whole compound word, as four-in-hands; forget-me-nots; court-yards; spoonfuls; green-houses; etc. But when one of the parts is more important than the others, the s is added to the more important part, thus: