(1)You must keep your dog()a lead on the street.(2)I do not want to go out because()the bad weather.根据句意用适当的介词或副词填空

1 on
2 of

keep on:保持
because of:因为

You must keep your dog on a lead in the park.
on
在公园里要牵着你的狗.
第二个
I do not want to go out because()the bad weather.
of
因为坏天气我不想出去

form
keep...form...
of
because of 都是词组