这些名词均有“孩子”之意。
baby : 日常用词，一般指从刚出生的婴儿到满两岁的或非常小的孩子，常含钟爱意味。
- The baby's crying!
婴儿在哭！ - a newborn baby
新生儿 - My sister's expecting a baby.
我姐姐怀孕了。 - She had a baby last year.
她去年生了个孩子。 - a baby boy/girl
男婴；女婴 - baby food/clothes
婴儿食品 / 服装
child : 普通用词，含义广，无感情色彩。泛指从胎儿、婴儿到10岁左右的儿童。
- an eight-year-old child
8岁的小孩 - As a child I didn't eat vegetables.
我小时候不爱吃蔬菜。 - A small group of children waited outside the door.
一小群孩子在门外等候。 - Both her children are now married with children of their own.
她的两个孩子都结了婚，有了自己的孩子。 - Jan is married with three young children.
简已婚，有3个孩子。
infant : 书面用词，狭义指出生后到两岁的小孩，广义指7岁以下的孩子；法律上则指未到法定年龄。北美英语中infant仅指婴儿，尤指新生儿。
- a newborn infant
新生儿 - a nursery for infants under two
两岁以下婴幼儿的托儿所 - their infant son
他们幼小的儿子 - She was seriously ill as an infant.
她年幼时曾患重病。 - the infant mortality rate
婴幼儿死亡率 - Mozart was an infant prodigy (= a child with unusual ability) .
莫扎特是个神童。
youngster : 泛指任何年龄的儿童或者少年，多指男孩，多为年长者的使用。
- The scheme is for youngsters between the ages of ten and 16.
该方案适用于年龄介于10至16岁之间的少年儿童。 - The camp is for youngsters aged 8 to 14.
这次夏令营是为8至14岁的少年儿童安排的。 - Other youngsters are not so lucky.
其他的孩子则没有这么幸运。 - Having an active youngster about the house can be quite wearing.
家里有个好动的小孩会是相当累人的。
