Why does the Torah add the words "u'Teme'im Yih'yu lachem"?
Rashi To teach us that, if the owner wishes to retain the Tamei vessel, he may do so.
The Torah already taught that a Tamei Kli Cheres must be broken. Why does it teach about breaking an oven?
Moshav Zekenim: "Yutatz" teaches that it suffices to break it so it cannot be used. One need not break it into small pieces.
Moshav Zekenim: It teaches that it receives Tum'ah even though it is attached [to the ground].