1.
将下列推理过程填写完整.
\((1)\)如图\(1\),已知\(∠B+∠BED+∠D=360^{\circ}\),求证\(AB{/\!/}CD\).
证明:过\(E\)点作\(EF{/\!/}CD(\)过直线外一点有且只有一条直线与已知直线平行\(){∵}EF{/\!/}CD\)
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\(∴∠D+∠DEF=180^{\circ}\),\((\)______________________________\()\)
\(∵∠B+∠BED+∠D=360^{\circ}\),\((\)已知\()\)
\(∴∠B+∠BEF=∠B+∠BED+∠D-(∠D+∠DEF)=360^{\circ}-180^{\circ}=180^{\circ}{∴}EF{/\!/}AB{,}(\)_______________________________________\(){∴}\)
______\({/\!/}\) ______ ,\((\) _____________________________________________________\()\)
\((2)\)如图\(2\),已知\(∠BED=∠B+∠D\),求证\(AB{/\!/}CD\).
证明:过\(E\)点作\(EF{/\!/}CD(\)过直线外一点有且只有一条直线与已知直线平行\(){∵}EF{/\!/}CD\)
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\({∴∠}D{=∠}FED{,}(\)____________________________________\()\)
\(∵∠BED=∠B+∠D\),\((\)已知\(){∴∠}B{=∠}BEF{-∠}D{=∠}BED{-∠}FED{=∠}BEF\)
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\({∴}\) ______\({/\!/}\) ______ ,\((\)______________________________\(){∴}\)
______\({/\!/}\) ______\({.}(\) __________________________________________________\()\)