___must come first and carefulness is the ___safe driving.A,safe; key of B,being safe,key ofC,safe,key to D,driving safely,key to

___must come first and carefulness is the ___safe driving.A,safe; key of B,being safe,key ofC,safe,key to D,driving safely,key to
___must come first and carefulness is the ___safe driving.
A,safe; key of B,being safe,key of
C,safe,key to D,driving safely,key to

___must come first and carefulness is the ___safe driving.A,safe; key of B,being safe,key ofC,safe,key to D,driving safely,key to
D.
driving safely 动名词短语做主语,safe形容词不做主语
key to　(key后面介词固定用to 表示“.的钥匙/关键所在”
整句翻译：安全驾驶第一,仔细是安全驾驶的关键所在.

D

D吧

D, driving safely, key to
driving safely是动名词短语作主语,
the key to ... "...的关键"

D

D

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