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风筝的竖线 = garis menegak wau 这个风筝形左右两边一样：左上斜边和右上斜边一样长，左下和右下也一样长。沿着中间的竖线对折，左右会完全重合，所以竖线是对称轴。 例子：Hana 的纸风筝就是从这条线对折的。 注意：风筝形的横线不是对称轴，因为上半短、下半长。

upright line on a kite = garis menegak wau This kite shape is the same on both sides: the upper-left and upper-right edges are equal, and so are the lower-left and lower-right edges. Folding on the upright middle line makes the halves match exactly, so the line is a line of symmetry. Example: Hana's paper kite was folded along exactly this line. Watch out: the flat line across a kite is not a line of symmetry, because the top part is short and the bottom part long.

长方形的横线 = garis mengufuk segi empat tepat 这条横线刚好在长方形高度的正中间。把上半折下来，上半和下半一样宽、一样高，完全重合，所以它是对称轴。长方形有 2 条对称轴：这条横的和一条竖的。 例子：把一张明信片上下对折，边会完全对齐。 注意：横线要在正中间，偏上或偏下都不行。

flat line on a rectangle = garis mengufuk segi empat tepat This flat line sits exactly halfway up the rectangle. Folding the top half down, the two halves are equally wide and equally tall, so they match exactly and the line is a line of symmetry. A rectangle has 2 lines: this flat one and an upright one. Example: folding a postcard top to bottom makes its edges line up neatly. Watch out: the flat line must be exactly in the middle; too high or too low will not work.

长方形的斜线 = garis serong segi empat tepat 沿长方形的对角线折，折过去的三角形会有一个角露在外面，和下面的三角形不重合。所以这条斜线不是对称轴。这是最常见的错误：两半面积一样大，但形状对不上。 例子：试着把一张长方形的纸沿对角线折，就会看到角跑出来。 注意：“一样大”不代表“完全重合”。

slanting line on a rectangle = garis serong segi empat tepat Folding a rectangle along its diagonal leaves one corner of the folded triangle sticking out, so it does not match the triangle underneath. This slanting line is therefore not a line of symmetry. It is the most common mistake: the two halves have equal area, but their shapes do not line up. Example: fold a rectangular sheet corner to corner and watch a corner poke out. Watch out: equal size does not mean an exact match.

箭头的竖线 = garis menegak anak panah 这个箭头朝上，箭头左边的尖角和右边的尖角一样，箭杆左右也一样宽。沿中间竖线对折，左右完全重合，所以是对称轴。箭头头大尾小没关系，比的是左边和右边。 例子：交通标志上直走的箭头也是左右对称的。 注意：对称是比较线的两边，不是比较上面和下面。

upright line on an arrow = garis menegak anak panah This arrow points up; its left and right barbs are the same, and its shaft is equally wide on both sides. Folding on the upright middle line makes the halves match exactly, so it is a line of symmetry. The head being bigger than the tail does not matter; we compare left with right. Example: the straight-ahead arrow on a road sign is also symmetrical left to right. Watch out: symmetry compares the two sides of the line, not the top with the bottom.

T 形的横线 = garis mengufuk bentuk T 这条横线在 T 字高度的中间，但是上半是宽宽的一横，下半是窄窄的一竖，形状不一样。往下折，宽的那一横会露出来，不能完全重合，所以横线不是对称轴。T 字只有中间 1 条竖的对称轴。 例子：字母 T 左右对称，上下不对称。 注意：线在中间不代表就是对称轴，要看两边形状。

flat line on a T shape = garis mengufuk bentuk T This flat line is halfway up the T, but the top half is a wide bar and the bottom half is a narrow stem, so the shapes differ. Folding down, the wide bar sticks out and cannot match, so the flat line is not a line of symmetry. The T has just 1 line, the upright one in the middle. Example: the letter T is symmetrical left to right but not top to bottom. Watch out: a line in the middle is not automatically a line of symmetry; compare the shapes on both sides.

正五边形的对称轴 = paksi simetri pentagon 正五边形有 5 条边，正多边形的对称轴数等于边数，所以有 5 条。每条对称轴都从一个顶点出发，穿过对面那条边的中点。选 1 是只看到竖的那一条。 例子：五角星形状的饼干也有 5 条对称轴。 注意：画对称轴时每个顶点都要试一次。

lines of symmetry of a pentagon = paksi simetri pentagon A regular pentagon has 5 sides, and a regular polygon has as many lines of symmetry as sides, so it has 5. Each line starts at a corner and passes through the middle of the opposite side. Choosing 1 sees only the upright line. Example: a five-pointed star biscuit also has 5 lines of symmetry. Watch out: when drawing lines of symmetry, try one from every corner.

刚好一条 = tepat 1 paksi 房子只有中间竖的 1 条对称轴，屋顶左右一样，但上下不一样。正方形有 4 条，太多了。平行四边形一条都没有。“tepat 1”就是刚好 1 条，所以答案是房子。 例子：等腰三角形、风筝形也都刚好有 1 条对称轴。 注意：先数清楚每个图形的对称轴，再对题目要求的数字。

exactly one = tepat 1 paksi The house has only the 1 upright line down the middle: its roof matches left and right, but its top and bottom differ. The square has 4 lines, too many, and the parallelogram has none. “Tepat 1” means exactly one, so the answer is the house. Example: an isosceles triangle and a kite also have exactly 1 line of symmetry. Watch out: count each shape's lines first, then compare with the number the question asks for.

画对的对称轴 = paksi simetri yang betul 这个三角形两条斜边一样长，对称轴从尖顶直直往下，经过底边的中点。横线把三角形分成上面小三角形和下面梯形，形状不一样；斜线也分不出两个一样的部分。所以只有竖线对。 例子：画对称轴时，先找“尖顶”和“底边中点”，再用尺连起来。 注意：画对称轴一定要用尺，线要直。

the correctly drawn line = paksi simetri yang betul This triangle has two equal slanted sides, so its line of symmetry runs straight down from the top point through the middle of the base. The flat line splits it into a small triangle and a trapezium of different shapes, and the slanting line does not make two matching parts either. Only the upright line is right. Example: to draw it, find the top point and the middle of the base, then join them with a ruler. Watch out: always use a ruler so the line is straight.

梯形的对称轴 = paksi simetri trapezium 这个梯形上边短、下边长，两条斜边一样斜。竖着从中间对折，左右完全重合，这是 1 条对称轴。横着折，上窄下宽，对不上。所以一共只有 1 条。选 2 是把横线也算进去了。 例子：灯罩的侧面常是这种梯形，左右对称。 注意：上下两条边不一样长，横线就不是对称轴。

lines of symmetry of a trapezium = paksi simetri trapezium This trapezium has a short top, a long bottom and two equally sloping sides. Folding upright down the middle makes the halves match exactly, which gives 1 line. Folding flat, the narrow top cannot match the wide bottom. So there is only 1 line; choosing 2 wrongly adds the flat line. Example: the side of a lampshade is often this kind of trapezium, symmetrical left to right. Watch out: when the top and bottom edges differ, the flat line is not a line of symmetry.

长方形的对称轴 = paksi simetri segi empat tepat 长方形竖着对折会重合，横着对折也会重合，所以有 2 条对称轴。两条对角线折起来会露出角，不算。选 4 就是把对角线也算进去了，那是正方形才有的。 例子：书本、门、黑板都是长方形，都有 2 条对称轴。 注意：长方形 2 条，正方形 4 条，不要搞混。

lines of symmetry of a rectangle = paksi simetri segi empat tepat A rectangle matches when folded upright and also when folded flat, so it has 2 lines of symmetry. Its two diagonals leave corners sticking out, so they do not count. Choosing 4 includes the diagonals, which only a square has. Example: a door and a whiteboard are rectangles, each with 2 lines of symmetry. Watch out: a rectangle has 2 lines and a square has 4; do not mix them up.