Typographical and grammatical corrections, continued.

(It helps if I save all files)

SocialDistancing.md

@@ -108,8 +108,8 @@ assignment partner(s).***
     During a videoteleconference (VTC), regardless of the particular technology
     used, the mute button is key to preventing distractions (this is also true
     of audio-only teleconferences). Unless you're actively participating in the
-    conversation, it is considered good manners to mute your microphone unless.
-    When it become your turn to speak, unmute the microphone, and then re-mute
+    conversation, it is considered good manners to mute your microphone.
+    When it becomes your turn to speak, unmute the microphone, and then re-mute
     when you are finished. It is perfectly acceptable to remain unmuted for the
     duration of a back-and-forth conversation you are part of. It is obviously
     also acceptable to remain unmuted if you're the only person speaking.