1选择题
Look at the ruler. The pencil is about ______ long.
- A. 15 mm
- B. 15 cm
- C. 15 m
- D. 15 km
答案：B
解析：本题考查对常用长度单位（毫米、厘米、米、千米）实际意义的理解。铅笔长度通常用厘米(cm)表示，毫米(mm)太小，米(m)和千米(km)太大。易错点：学生可能混淆毫米和厘米的适用场景。
2选择题
What time is it in the afternoon if it is 3:00 p.m. in the 24-hour clock?
- A. 3:00
- B. 13:00
- C. 15:00
- D. 12:00
答案：C
解析：本题考查24时计时法。下午3时 = 12时 + 3时 = 15时。易错点：学生可能误选13:00（下午1时）。
3选择题
There are 8 apples. The number of oranges is 3 times the number of apples. How many oranges are there?
答案：B
解析：本题考查“倍的认识”。苹果有8个，橘子是苹果的3倍，所以橘子有 8 × 3 = 24个。易错点：误用加法（8+3=11）或减法。
4填空题
2 tons = ______ kilograms. (用阿拉伯数字填写)
答案：2000
解析：本题考查质量单位“吨”与“千克”之间的换算。1吨 = 1000千克，所以2吨 = 2 × 1000 = 2000千克。易错点：换算率记忆错误，或计算时漏写0。
5填空题
What fraction of the shape is shaded? (Look at a square divided into 4 equal parts, with 1 part shaded.) Write the answer in English words: ______
答案：one fourth / one quarter
解析：本题考查分数的初步认识。将一个正方形平均分成4份，阴影部分占其中的1份，用分数表示为1/4，读作 one fourth 或 one quarter。易错点：用中文填写，或分数读写错误。
6计算题
Calculate: 367 + 485 = ?
答案：852
解析：本题考查万以内加法（进位）。计算过程：个位7+5=12，写2进1；十位6+8+1=15，写5进1；百位3+4+1=8。结果是852。易错点：进位后忘记加到前一位的计算中。
7解答题
A rectangle has a length of 12 cm and a width of 5 cm. What is its perimeter?
答案：The perimeter is (12 + 5) × 2 = 17 × 2 = 34 cm.
解析：本题考查长方形周长计算公式：周长 = (长 + 宽) × 2。易错点：忘记乘以2，或者长度单位不统一（本题单位统一，无需换算）。
8应用题
Tom has 256 stickers. He gives 178 stickers to his friend. How many stickers does Tom have left? Use subtraction (破十法) to explain your thinking.
答案：Tom has 256 - 178 = 78 stickers left. Using the 'breaking ten' method: 256 - 178 = 256 - 180 + 2 = 76 + 2 = 78. (Method explanation: Subtract 180 (which is 178+2) first, then add back the 2.)
解析：本题综合考查万以内减法（退位）及对“破十法”思路的理解。常规竖式计算时，个位6减8不够减，需从十位退1当10。用破十法解释：256 - 178 = 256 - 180 + 2 = 76 + 2 = 78。易错点：退位时忘记在退位的数字上做标记，或计算过程出错。