Baboons(狒狒) live in Africa. They are like monkeys. Most people think daddy baboons don't know their babies. But scientists (科学家) find that daddy baboons know how to help their babies. The daddy baboons are smart.
Joan Silk is a scientist. She studies the baboons for 3 years. She says the daddy baboons are happy to see their babies. They have big teeth to help the babies to eat hard things. Mother baboons are small. And they live in a place. When a mother baboon gives birth(分娩), she often has only one baby. Baby baboons have fur. They are very cute.
During the day they eat things. At night, they sleep in the trees. Most children like baboons because they look like the man.

研究远古人类生产生活第一手资料是（　　）

组成细胞的化合物中，含量最多的有机化合物是（　　）

1919年6月5日，一个日资纱厂的工人突破租界巡捕的武装包围，举行罢工，声援学生运动；商务印书馆、中华书局的工人也参加进来，罢工达到高潮时，参加人数达六、七万。这场工人罢工斗争应发生在(    )