江西人教版选修六第五单元P35,butthisbeingmyfirstexperienceTHeothertwoclimbeddownintothecratertocollectsomelavaforlaterstudy,butthisbeingmyfirstexperience,Istayedatthetopandwatchedthem.but再接含逻辑主

Question

江西人教版选修六 第五单元P35 ,but this being my first experience
THe other two climbed down into the crater to collect some lava for later study,but this being my first experience,I stayed at the top and watched them.
but再接含逻辑主语的非谓语动词结构跟我以前学习的知识有冲突,
21.The secretary worked late into the night,___B__ a long speech for the president.
22.The secretary worked late into the night and __C___ a long speech for the president.
A.to prepare B.preparing C.prepared D.prepare
23.There _A__ some trouble over this in the past,I want to treat the matter carefully.
24.Because there _B__ some trouble over this in the past,I want to treat the matter carefully.
A.being B.was C.had been D.has been

Answer 1

额.我想.应该是这样.
一个单句里只能有一个动词,其他的动作则不能以动词而要以其他的形式出现.例句里面有一个连词but,所以可以看做是两个单句,可以出现两个动词,句中是climb和stay.所以be就只能以现在分词的形式出现了.
问题补充里面大致也可以根据这个来判断填写动词的什么形式.