THE ''GEMAORAH'' SAID THAT IS HE GAVE AND SHE SAID..... SO THEN WE DERIVE FROM THE BRAISA THAT IS A ''SOFEK......'' NOW I HAD THIS PROBLEM CUASE I REMEMBER LARNING IN Tosfos (daf 4:) that the only reson why we need the Gezeirah Shavah is to let us know that even when one use's money for ''kidushin'' we need that he should give to the woman and tell her also Harei At Mekudeshes Li so if we look at it the Gezeirah Shavah is from the torah (that one needs to give and say) so how could the gemorah say that it is a Safek if from the torah we need both the giving and the saying by the man
shemuel, new york usa
Tosfos possibly holds like the Ran's understanding of the Rif, which is endorsed by the Maharit, that when the Gemara says "Nasan Hu v'Amrah Hi" -- "he gave and she said" is a Safek, it doesn't mean that it is a real Safek, but rather that Chazal were stringent to require a Get in this case. However, the Gezeirah Shaveh stands mid'Oraisa.
All the best,
Yaakov Montrose