How do I fix the prompt ending with an asterisk sign without exiting hbase shell?

I know the commands in hbase shell need not end with a ';'.
In hbase shell, typing commands end with a ';' or incorrect characters would change the end of the prompt from '>' to an asterisk sign.
For example:

describe 'some_table';

or

"using right-key to copy text from putty"

The end of the prompt will change to an asterisk sign after running this command. This stops me from typing other commands.
How do I fix the prompt ending with an asterisk sign without exiting hbase shell?

/* edit my question    
Ctrl+D can stop an incomplete command in hbase shell.    
*/