1选择题
Look at the picture. The ruler is 15 _______ long.
- A. millimeters
- B. centimeters
- C. meters
- D. kilometers
答案：B
解析：本题考查长度单位的选择。图片中尺子长度通常用厘米（centimeters）描述，毫米（millimeters）太小，米（meters）和千米（kilometers）太大，不符合常识。易错点是混淆常用长度单位的大小。
2选择题
It's 3 o'clock in the afternoon. In 24-hour time, it is _______.
- A. 3:00
- B. 13:00
- C. 15:00
- D. 30:00
答案：C
解析：本题考查24时计时法。下午3时用24时计时法表示，需要加12，即15:00。易错点是忘记加12或加错。
3选择题
There are 24 students in Class A. Class B has 3 times as many students as Class A. How many students are in Class B?
答案：B
解析：本题考查“倍的认识”和多位数乘一位数。Class B的人数是Class A的3倍，即24×3=72。易错点是计算错误，特别是进位忘记加。
4填空题
The box weighs 2 tons. This is equal to _______ kilograms.
答案：2000
解析：本题考查质量单位换算。1吨等于1000千克，所以2吨等于2×1000=2000千克。易错点是忘记吨与千克之间的进率是1000。
5填空题
Calculate: 456 + 378 = _______
答案：834
解析：本题考查万以内加法（进位）。计算时需注意个位6+8=14，向十位进1；十位5+7+1=13，向百位进1；百位4+3+1=8。易错点是进位忘记加上。
6填空题
Calculate: 1002 - 567 = _______
答案：435
解析：本题考查万以内减法（退位）。计算时需注意个位2-7不够减，向十位借1，但十位是0，需连续向百位、千位借位。易错点是退位点标记不清导致计算错误。
7解答题
A rectangular garden is 12 meters long and 8 meters wide. What is the perimeter of the garden? Please show your calculation.
答案：Perimeter = (Length + Width) × 2 = (12 + 8) × 2 = 20 × 2 = 40 meters. The perimeter of the garden is 40 meters.
解析：本题考查长方形周长的计算。长方形周长公式为（长+宽）×2。易错点是公式记忆错误或计算过程出错。
8解答题
Tom ate 1/4 of a pizza, and Jerry ate 2/4 of the same pizza. How much of the pizza did they eat together? How much is left? Please write your answer in fractions.
答案：They ate 1/4 + 2/4 = 3/4 of the pizza together. The amount left is 1 - 3/4 = 1/4 of the pizza.
解析：本题考查分数的简单加减法。同分母分数相加，分母不变，分子相加。易错点是忘记分母不变，或计算剩余部分时出错。