As the flights grew longer, a new set of two collection bags was devised, 24 for liquid wastes and the other for solid wastes.
答案：(D) one
【句型】one...the other... 固定句型，表示「兩者中的一個……另一個……」（one for liquid, the other for solid）；the one（通常用於特指情況）、someone、no one 都不合這個「一個…另一個…」的對應句型。
四個選項長得很像，都繞著 one 打轉，最容易憑感覺挑 the one，覺得「特指那一個」比較精確。答對率不到五成。但這一格根本不必憑感覺，答案就寫在空格後面那半句裡。
四個選項都是代名詞，可見這一格考的是「兩者中的一個」該怎麼說，那就往後看。空格後面是 for liquid wastes and the other for solid wastes——the other 已經出現了。one... the other... 是兩者對應的組合：前面點名一個，後面用 the other 指剩下的那一個，掛鉤是國中就背過的 I have two pens. One is red; the other is blue.（我有兩枝筆，一枝是紅的，另一枝是藍的。）。句子前半的 a new set of two collection bags 也明說了是兩個，兩邊互相印證。這一題的鑑別度高達 68，是本批最高，分開的就是有沒有讀完後半句再回頭填。順便把整組分清楚：兩者用 one... the other...；三者以上任取一個用 one... another...；剩下的全部用 the others。
someone（某人）、no one（沒有人）：這兩個都只指人，而這裡講的是收集袋——先看指人還是指物，一次就刷掉兩個。the one（那一個）：the 表示已經在講定的某一個，需要前文先鎖定它；而這裡是第一次把兩個袋子分開來講，還沒有哪一個被指定過。
one... the other...（兩者中的一個……另一個……）、one... another...（三者以上的一個……另一個……）、the others（其餘的全部）、a set of（一組……）、be devised（被設計出來）、liquid／solid waste（液態／固態廢棄物）。
The first American space toilet was Alan Shepard's space suit. His flight was supposed to last only 15 minutes, so there was no provision made for him to relieve himself in the capsule. His flight, 21, was delayed for hours. It was then decided that Alan Shepard should relieve himself in his space suit, and continue with the mission as scheduled.
22 problem urged NASA to develop the first space toilet, a modified diaper. Diapers are 23 used by astronauts when they are outside the space shuttle, wearing a spacesuit.
As the flights grew longer, a new set of two collection bags was devised, 24 for liquid wastes and the other for solid wastes. Once used, the bags are sealed and stored for the flight back to the earth, 25 they are disposed of.