句型转换(Thank you)

1.We didn't reach the top because it was too hot.(改为简单句)
Because of the hot weather, we didn't reach the top.
2.He borrowed my book two months ago.(改为同意句)
He has kept my book for two months.
3.I collect toys (because they are beautiful).(就括号部分提问)
Why do you collect toys?
4.I wondered what I should do next.(改为同意句)
I wondered what to do next.
5.interesting\the\play\it's\with\to\cat(连词成句)
(It's interesting to play with the cat.)
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1 because of
2 has borrowed
3why do
4to do
5 it's interesting to play with the cat.