The road is covered with snow.I can't understand they insist on going by motorbi
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The road is covered with snow.I can't understand ________ they insist on going by motorbike.
A．why B．whether
C．when D．how
试题答案
A
考查宾语从句的用法。句意：路面上满是雪，我不明白他们为什么坚持骑摩托车。