Chapter 4, Mishna 1
What are the consequences of marrying someone whom it is prohibited to marry? Why is a convert like a scab? In what location do Jews have muddled lineage? Why don’t we pronounce yud hey vav hey? When was it said? Which families have presumption of flawed lineage? Who are the “people who lie upon beds of ivory”? Are there any Jews with completely unflawed lineage? Why is it good to be silent? What is relevance of location of bridge over Euphrates?