1they have kept （）on this project for thrree years ( work )2the children will climb the hill if it ( ) tomorrow A won,t rain B didn,t rain Cdoesn,t rain D isn,t raining 3Neither his father nor he ( ) the island A has been to Bhas gone to C have been to Dhave gone to
问题描述：
1they have kept （）on this project for thrree years ( work )
2the children will climb the hill if it ( ) tomorrow A won,t rain B didn,t rain Cdoesn,t rain D isn,t raining 3Neither his father nor he ( ) the island A has been to Bhas gone to C have been to Dhave gone to
答
working
doesn't rain
has been to
答
1 working ( keep doing sth )
2 C ( if 引导的从句是主将从现
3 A ( 主语是三单,排除C； 而HAS GONE TO 人不在这里,去了某地了）
加油!不明白再问!