<p>Does it make sense to say "My friend's uncle's house" or "Her mother's friend's book"? Is this grammatically correct??</p>
<p>Also, when is "and so" used, instead of "therefore" or "so"?</p>
<p>Thanks</p>
<p>Yes.</p>
<p>You should not, unless writing informally, begin a sentence with “And.” “Therefore” is a more formal word than “and so” and is less narrative: “I was running really fast to catch my bus, someone stuck his leg out, and so I fell and broke my leg.” You probably wouldn’t use “therefore” in that sentence, even though it would make sense (for correct grammar in that sentence, you would need a semicolon before “therefore,” which is not needed with a clause that begins with “and”). Whether you use “and” before so depends on your sentence and your style.</p>
<p>“And so” is colloquial and used in everyday spoken speech, but it is not grammatically correct. Use “so” instead.</p>