Update bot-builder-basics.md (#317)

Incorporate grammar bot feedback.

Author: johnataylor

articles/v4sdk/bot-builder-basics.md

@@ -36,7 +36,7 @@ Let's drill into the previous diagram with a focus on the arrival of a Message A
 
 ![activity processing stack](media/bot-builder-activity-processing-stack.png)
 
-In the echo example, the bot replied to the Message Activity with another Message Activity containing the same text message. The Message Activity generated in response must be correctly addressed. Otherwise, it won’t arrive at its intended destination. Correctly addressing an Activity means including the appropriate ConversationReference details along with details about the sender and the recipient. In this particular example, the Message Activity is sent in response to one that had arrived. Therefore, the addressing details can be taken from the inbound Activity. In general, this is not something application need be concerned about as it handled by the SDK behind the scenes. However, it can be useful to know when debugging and examining traces or audit logs.
+In the echo example, the bot replied to the Message Activity with another Message Activity containing the same text message. The Message Activity generated in response must be correctly addressed. Otherwise, it won’t arrive at its intended destination. Correctly addressing an Activity means including the appropriate ConversationReference details along with details about the sender and the recipient. In this particular example, the Message Activity is sent in response to one that had arrived. Therefore, the addressing details can be taken from the inbound Activity. In general this is handled by the SDK behind the scenes. In most cases your application will not need to handle this explicitly. However, it can be useful to know when debugging and examining traces or audit logs.
 
 In the echo bot example, the bot created and sent a Message Activity on an HTTP POST in response to the inbound Message Activity it had received on the HTTP POST it was handling. However, there is nothing in the protocol that mandates this exchange. It’s common for a bot to respond to a ConversationUpdate Activity by sending some welcome text in a Message Activity.