<s>
Retrospective	B-General_Concept
think	I-General_Concept
aloud	I-General_Concept
protocol	O
is	O
a	O
technique	O
used	O
in	O
usability	B-General_Concept
,	O
and	O
eye	B-General_Concept
tracking	I-General_Concept
in	O
particular	O
,	O
to	O
gather	O
qualitative	O
information	O
on	O
the	O
user	O
intents	O
and	O
reasoning	O
during	O
a	O
test	O
.	O
</s>
