Cub Scouts, with the help of parents, build their own cars from wood, usually from kits 11 a block of pine, plastic wheels, and metal axles.
答案：(C) containing
【句型】containing 為現在分詞片語，修飾前面的 kits（套件），表示「內含一塊松木、塑膠輪子與金屬車軸的套件」，kits 與 contain 之間為主動關係（套件包含這些零件）；contain（原形動詞不能直接修飾名詞）、contained（過去分詞表被動，語意不合）、to contain（不定詞不符此處修飾語境）皆不符合。
本題大考中心未公布逐題答對率，以下不談數據，只談觀念。
四個是同一個字的不同形態，會讓人立刻進入文法模式；又因為主要子句已經有動詞 build，很多人會想「這裡應該是不定詞表目的」而選 to contain。
先看空格前後：前面是名詞 kits，後面是三個並列的名詞（a block of pine, plastic wheels, and metal axles）。整句的主要動詞 build 已經有了，空格不可能再放一個限定動詞，contain 先出局。剩下的問題是「掛在 kits 後面的修飾語該用哪一種形態」。用修飾語後置的通則：分詞單獨一個時放在名詞前面（a barking dog、a broken window），一旦後面還帶著受詞，整串就得移到名詞後面（the man standing there）。這裡分詞後面帶著三個名詞，當然要放在 kits 後面。再分主動被動：kits 是「內含」這些零件的一方，是主動關係，所以用現在分詞 containing，還原成關係子句就是 kits that contain a block of pine ...。
contained 是過去分詞、走被動關係，還原成 kits that are contained（被裝在裡面的套件），主客顛倒了——被裝進去的是木塊與輪子，不是套件。to contain 表目的或還沒發生的事，但套件不是「為了要內含零件」才做出來的，它本來就內含這些零件，講的是既有的狀態。contain 是原形，句中已有主要動詞，不能再放一個。
kits containing ＋ 名詞（內含……的套件）、a block of wood（一塊木頭）、build A from B（用 B 做出 A）、a barking dog（吠叫的狗，分詞單獨一個放名詞前面）、the man standing there（站在那裡的那個人，分詞帶了東西就放名詞後面）、axle（車軸）
The Pinewood Derby is a racing event for Cub Scouts in the Boy Scouts of America. Cub Scouts, with the help of parents, build their own cars from wood, usually from kits 11 a block of pine, plastic wheels, and metal axles.
Cub Master Don Murphy organized the first Pinewood Derby, held May 15, 1953 in Manhattan Beach, California. Murphy's son was too young to participate in the popular Soap Box Derby races, so he 12 the idea of racing miniature wooden cars.
The Scout is given a block of wood made of pine 13 two notches for wheels, four plastic wheels, and four nails. The finished car must use all nine pieces, must not exceed a certain weight, must not exceed a certain length and must fit on the track. Each 14 is able to carve and decorate the car as he chooses.
The great thing about the race is that the boys build the cars with their dads, grandfathers, or 15 they choose. It's not about winning or losing; it is about having the quality time with each other and enjoying a great day with family, friends and smiling faces.