【C13】A．yetB．andC．beforeD．when

When does education begin？ 查看材料A.Before one enters

【C13】A．butB．andC．soD．even

【C13】A．YetB．As a resultC．AlsoD．For example

【C13】A．whenB．ifC．beforeD．since

_________(53)A.when B.after C.before D.until

_________(53)A.when B.afterC.before D. until