可以的,因为主句从句主语一致,可以省略从句的主语和谓语动词,但是这个谓语动词好像应该只能是be动词.
Although (it is) only 1 or 2 inches long,the bumblebee bat is a mammal and,therefore,akin to elephants and whales.
When (he was) doing his homework,he heard a bird singsing.
可以的,因为主句从句主语一致,可以省略从句的主语和谓语动词,但是这个谓语动词好像应该只能是be动词.
Although (it is) only 1 or 2 inches long,the bumblebee bat is a mammal and,therefore,akin to elephants and whales.
When (he was) doing his homework,he heard a bird singsing.