Error and correction.

The last time list.

10 print 1+2
20 print "Hello BASIC!"

If there was spelling mistake in the list like a below,

20 primt "Hello BASIC!"

If you run in this state then,

Syntax error in 20
So, it'll became an error.

In this case, after inputting properly 'm' to 'n',
and push Enter-key to correct.

Also, when want only to delete line 20,
20 [Enter]

10 print 1+2

In this way, by line number only input,
The line is deleted.