Extend a line

Often, a complete line feature can't be drawn in a single segment. For example, a highway might pass through several cities, so it would need to be drawn as multiple road segments. You can use the Extend option to associate multiple segments of the highway with one another.

While drawing linear features from dead-ends or intersections, you'll be prompted to either extend the existing segment or create a new one.

Extend route: This creates a line with the same attributes as the previous section.

Create a new road: This creates a new line with default details.

It's important to select the correct options when extending a segment, because the information will be used in driving directions and search results.

Extending a road

Use Extend to associate a line segment with part of an existing road. 
Click Add new and select Draw a Line and choose the category "Road" from the drop-down. 
Place the first point at the edge of the existing road. Double-click or click Enter to finish drawing. 
The info window that appears will allow you to either extend the existing road, create a new feature, or do both. 

Select "Extend the existing road" and click Next. 
Edit the attributes in the left panel if necessary and click Save.

Multiple extensions of a road

Sometimes a long road while passing through cities or villages also has a local name. Here's how to add a different name to this section of the road: 
Draw the part of the road that needs a separate name. As seen below, select both the "Extend MDR 58" and "Create new road" options: 

Add the local name of that section of the road in the "Name" field. Note that you won't see any option to edit or remove the original name (in this case, "MDR 58"). 

To extend "MDR 58" without extending "Asop Road," unselect it in the pop-up. 

These steps let you create a separate name for local sections of the road while retaining the original name and attributes of the highway.
Best Practices 
You can use the Select Road Segments tool to add local names for a road that's already been drawn. 
Make sure you select the correct road while extending to avoid the creation of inaccurate directions. In general, all the roads that you extend appear as 'Added Route' under feature details. 
If you change the attributes of the extended road, the changes will not propagate to the already published road. For example: if you change the attributes 'Accuracy' & 'Divider' for the extended road, those attributes will not be changed for the pre-existing section of the road.