你这个也太难回答了吧!
pen:fountain pens,pencil,ballpoint/ball-pen,gel pen,color pencil,Chinese brush
也可以把书法：calligraphy,文房四宝,砚等归类.
brother:sister,cousin,parent,father,mother,grandpa/grandfather,grandma/grandmother...
太多了,这些词都可以加上hood.
january:词典上把十二个月份的和四个季节的词写下来.
train:car,lorry,sub-way,metro,bycicle,bus,minibus,van,wheelbarrow,handcart,truck...
你可以把油啊,气啊,轮胎啊,方向盘刹车气囊等等等等等总结下来,如果你喜欢.
cloud:rain,sun,snow,,lightning,thunder,storm,flood,typhoon,landslide,hurricane,num,cold,chilly,cool,hot,stroke.好多好多啊,你把表示恶劣天气和冷热程度不同的词都可以总结.
monkey就更别提了,把所有动物的词想到什么就写什么呗：tiger,turtle/tortoise,crocodile,fish,cormorant,snake ,dog,fog,fox,eagle.
记得给分哦.