He has four books full of stamps!他有四本装满邮票的集邮册。
full of充满,装满。
full of stamps在这里是后置定语,用来修饰books。
e.g.车里挤满了人。
The bus is full of people.我有满满一篮子花。

I have a basketball full of flowers.be full of=filled with
瓶子里装满了牛奶。
The bottle is full of milk.
The bottle is filled with milk.

Finally, it's Danny's turn.
终于,轮到了丹尼。
句型t's one's turn to do sth.表示“轮到某人做某事了”。
e.g.轮到吉姆做家务了。
It's Jim's turn to do housework.
注意:提问“轮到谁做某事”时,英语要用whose.e.g.该轮到谁值日了?
Whose turn is it to be on duty?