First of all you need to familiar with Razor.

You can consider dynamic email template as a macro that use Razor engine. 

The difference between macro and dynamic email template are:

1. In email template there is no current page, so you can't access umbraco content through currentPage

2. Package provide a external method "Arguments" to retrieve arguments are passed to email template.

There are two email sending method in package:

1. automatically, In this way Arguments() will return a dynamic object contain 4 properties.

Email - return current email to address

EmailSource - return a value to indicated where is email to address come from. 

1 -- email come from member group

2 -- email come from subscribe

MemberGroupID - return member group id if have

SubscribeTypeID - return subscribe type unique id if have

2. manually, In this way Arguments() will return a dynamic object you passed.

Following is a sample:

Dear @this.Arguments().Email:
    Thanks for your register. In order to complete your registration you need to verify your email address:
    Click to verify email address
Regards,
uWebZone