The Dove

The poem 'The Dove' written by John Keats is prescribed for SSLC. The lines 3,4 and 5 are different from the original version. The lines in the textbook are as follows:

O, what could it grieve for? it was tied,
With a single thread of my own hand's weaving;
Sweet little red feet, why should you die?

But in the original version, these lines are as follows:

O what could it grieve for? Its feet were tied

With a silken thread of my own hand’s weaving:

Sweet little red feet! Why would you die?

For clarification, click the link below:
http://mural.uv.es/ancampe/keats.html