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长方体分类 = kelaskan kuboid 长方体有两个一样的长方形底面，一前一后相对；6 个面全是平的。两个条件都符合，所以长方体是棱柱。它是立体图形，不是平面的正多边形。 例子：一块砖、一个纸巾盒都是长方体。 注意：正多边形是平面图形，立体图形不能叫正多边形。

classifying a cuboid = kelaskan kuboid A cuboid has two matching rectangle bases facing each other, front and back, and all 6 of its faces are flat. It meets both conditions, so a cuboid is a prism. It is a solid, not a flat regular polygon. Example: a brick and a tissue box are both cuboids. Watch out: regular polygons are flat shapes; a solid cannot be called a regular polygon.

金字塔分类 = kelaskan piramid 金字塔的面虽然全是平的，但它只有 1 个正方形底面，4 个三角形往上聚成一个尖顶，没有两个相对的一样底面。所以金字塔不是棱柱。 例子：三角锥也不是棱柱，原因一样。 注意：所有面都平还不够，还要有两个一样的底面。

classifying a pyramid = kelaskan piramid All the faces of a pyramid are flat, but it has only 1 square base, with 4 triangles meeting at a point on top, so there are no two matching bases facing each other. That is why a pyramid is not a prism. Example: a triangular pyramid is not a prism either, for the same reason. Watch out: flat faces alone are not enough; a prism also needs two matching bases.

找出不是棱柱的 = cari yang bukan prisma 正方体和三角棱柱都有两个一样的底面、所有面都是平的，是棱柱。圆锥有一个弯曲的面和一个尖顶，只有一个圆形底面，所以不是棱柱。 例子：冰淇淋甜筒是圆锥形。 注意：题目问的是“bukan”（不是），别选成棱柱。

finding the non-prism = cari yang bukan prisma The cube and the triangular prism both have two matching bases and only flat faces, so they are prisms. The cone has a curved surface, a pointed tip and only one circle base, so it is not a prism. Example: an ice-cream cone is cone-shaped. Watch out: the question asks which is “bukan” (not) a prism, so do not pick a prism.

三角棱柱的面 = permukaan prisma segi tiga 三角棱柱前后各有 1 个三角形底面，共 2 个；侧面有 3 个长方形。所以平面一共 2 + 3 = 5 个。选 6 是当成了长方体；选 3 是只数了长方形。 例子：长方体有 2 + 4 = 6 个面。 注意：看不到的后面那个三角形也要数。

faces of a triangular prism = permukaan prisma segi tiga A triangular prism has 1 triangle base at the front and 1 at the back, 2 in all, plus 3 rectangle sides. So it has 2 + 3 = 5 flat faces. Choosing 6 treats it like a cuboid, and choosing 3 counts only the rectangles. Example: a cuboid has 2 + 4 = 6 faces. Watch out: count the hidden triangle at the back too.

三角棱柱的棱 = tepi prisma segi tiga 前面的三角形有 3 条棱，后面的三角形也有 3 条，再加上连接前后的 3 条长棱，一共 3 + 3 + 3 = 9 条。选 6 是漏了中间连接的 3 条；12 是长方体的棱数。 例子：正方体的棱：4 + 4 + 4 = 12 条。 注意：虚线表示看不到的棱，也要算。

edges of a triangular prism = tepi prisma segi tiga The front triangle has 3 edges, the back triangle has 3 more, and 3 long edges join front to back, giving 3 + 3 + 3 = 9 edges. Choosing 6 misses the 3 joining edges, and 12 is the number for a cuboid. Example: a cube's edges are 4 + 4 + 4 = 12. Watch out: dashed lines show hidden edges, and they count too.

三角棱柱的顶点 = bucu prisma segi tiga 前面的三角形有 3 个顶点，后面的三角形也有 3 个，一共 3 + 3 = 6 个。选 3 是只数了前面；8 是长方体或正方体的顶点数。 例子：正方体前面 4 个、后面 4 个，共 8 个顶点。 注意：被挡住的顶点也要数进去。

vertices of a triangular prism = bucu prisma segi tiga The front triangle has 3 vertices and the back triangle has 3 more, so there are 3 + 3 = 6. Choosing 3 counts only the front, and 8 is the number for a cube or cuboid. Example: a cube has 4 vertices at the front and 4 at the back, 8 in all. Watch out: count the hidden vertices as well.

正方体的棱 = tepi kubus 正方体前面一圈 4 条棱，后面一圈 4 条，再加上连接前后的 4 条，一共 12 条。8 是顶点数，6 是面数，这三个数字很容易搞混。 例子：长方体的棱也是 12 条。 注意：棱（tepi）、顶点（bucu）、面（permukaan）要分清。

edges of a cube = tepi kubus A cube has a ring of 4 edges at the front, 4 at the back and 4 joining front to back, 12 in all. 8 is the number of vertices and 6 the number of faces; these three numbers are easy to mix up. Example: a cuboid also has 12 edges. Watch out: keep edges (tepi), vertices (bucu) and faces (permukaan) clear in your mind.

长方体的顶点 = bucu kuboid 长方体前面 4 个顶点，后面 4 个顶点，一共 8 个。12 是棱的数目，6 是面的数目。顶点是几条棱相交的那个点。 例子：正方体也有 8 个顶点。 注意：数顶点时可以在每个角点一下，免得漏掉后面的角。

vertices of a cuboid = bucu kuboid A cuboid has 4 vertices at the front and 4 at the back, 8 in all. 12 is the number of edges and 6 the number of faces. A vertex is the point where edges meet. Example: a cube also has 8 vertices. Watch out: tap each corner as you count so the hidden back corners are not missed.

六边形的边 = sisi heksagon 正六边形 heksagon 有 6 条一样长的边，像蜂巢的格子。5 条边是五边形，7 条边是七边形。 例子：用 6 根一样长的牙签可以围成一个正六边形。 注意：heksagon（6）和 heptagon（7）不要搞混。

sides of a hexagon = sisi heksagon A regular hexagon has 6 equal sides, like a honeycomb cell. A shape with 5 sides is a pentagon, and one with 7 sides is a heptagon. Example: 6 toothpicks of equal length can make a regular hexagon. Watch out: do not mix up heksagon (6) and heptagon (7).

七边形的顶点 = bucu heptagon heptagon 有 7 条边。多边形的顶点数等于边数，所以也有 7 个顶点。6 是六边形，8 是八边形。 例子：五边形 5 条边、5 个顶点。 注意：数顶点时从一个角开始，绕一圈回来就停。

vertices of a heptagon = bucu heptagon A heptagon has 7 sides, and a polygon has as many vertices as sides, so it has 7 vertices. 6 belongs to the hexagon and 8 to the octagon. Example: a pentagon has 5 sides and 5 vertices. Watch out: start at one corner and stop when you are back where you began.

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。每条都从一个顶点穿到对面边的中点。选 1 是只看到了竖的那条。 例子：正六边形有 6 条对称轴。 注意：每个顶点都要试一条线。

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 runs from a corner to the middle of the opposite side. Choosing 1 sees only the upright line. Example: a regular hexagon has 6 lines of symmetry. Watch out: try a line from every corner.

长方形的斜线 = garis serong segi empat tepat 沿长方形的对角线折，折过去的三角形会露出一个角，跟下面不重合，所以不是对称轴。从顶点到顶点的线不一定是对称轴。长方形只有 2 条对称轴（横、竖），不是 4 条。 例子：正方形的对角线才是对称轴。 注意：这是这个单元最容易错的题。

slanting line on a rectangle = garis serong segi empat tepat Folding a rectangle along its diagonal makes the folded triangle poke out a corner, so it does not match and is not a line of symmetry. A corner-to-corner line is not automatically a line of symmetry. A rectangle has only 2 lines (flat and upright), not 4. Example: only a square's diagonals are lines of symmetry. Watch out: this is the most commonly missed question in the unit.

T 形的对称轴 = paksi simetri bentuk T T 形竖着从中间对折，左右完全重合，这是 1 条对称轴。横着折，上面宽、下面窄，对不上。斜着折也不行。所以只有 1 条。 例子：字母 A 也只有 1 条竖的对称轴。 注意：每一种折法都试过，才能确定条数。

lines of symmetry of a T shape = paksi simetri bentuk T Folded upright down the middle, the T shape matches exactly, giving 1 line of symmetry. Folded flat, the wide top cannot match the narrow bottom, and a slanting fold fails too. So there is only 1 line. Example: the letter A also has just 1 upright line of symmetry. Watch out: try every kind of fold before deciding how many lines there are.

不是正多边形 = bukan poligon sekata 正多边形的每条边都一样长。五边形、正方形都符合。长方形的长边和短边不一样长，所以不是正多边形。 例子：A4 纸是长方形，方形便条纸才是正方形。 注意：题目问“bukan”，要选不符合的那一个。

not a regular polygon = bukan poligon sekata Every side of a regular polygon is the same length. The pentagon and the square both fit. A rectangle's long and short sides differ, so it is not a regular polygon. Example: an A4 sheet is a rectangle, while a square sticky note is a square. Watch out: the question asks for “bukan”, so choose the one that does not fit.

字谜：对称轴 = silang kata: paksi simetri 把图形分成一样两半的折线，叫 paksi simetri（对称轴）。答案 SIMETRI，正好 7 个字母。SEKATA 是“正（多边形）”的意思，只有 6 个字母；PRISMA 是棱柱。 例子：paksi simetri 可以是竖线、横线或斜线。 注意：填字谜时先数格子有几个，再对字母数。

crossword: line of symmetry = silang kata: paksi simetri The fold line that splits a shape into two matching halves is the paksi simetri, so the answer is SIMETRI, exactly 7 letters. SEKATA means regular and has only 6 letters, and PRISMA means prism. Example: a paksi simetri can be upright, flat or slanting. Watch out: in a crossword, count the boxes first and match the number of letters.

字谜：正方体 = silang kata: kubus 6 个面全是正方形的立体是正方体，马来文 KUBUS，5 个字母，K 开头 S 结尾，正好填进格子。KUBOID 是长方体，有 6 个字母；KON 是圆锥。 例子：骰子的形状就是 kubus。 注意：kubus 和 kuboid 只差几个字母，意思不同。

crossword: cube = silang kata: kubus The solid with 6 square faces is the cube, KUBUS in Malay: 5 letters, starting with K and ending with S, so it fits the boxes. KUBOID is the cuboid with 6 letters, and KON is the cone. Example: a dice has the shape of a kubus. Watch out: kubus and kuboid differ by only a few letters but mean different shapes.

字谜：八边形 = silang kata: oktagon 8 条边的正多边形是 OKTAGON，7 个字母。HEPTAGON 是七边形，PENTAGON 是五边形，而且它们都是 8 个字母，填不进 7 个格子。 例子：“停”字交通牌是 oktagon。 注意：用格子数也能帮你检查答案。

crossword: octagon = silang kata: oktagon The regular polygon with 8 sides is OKTAGON, which has 7 letters. HEPTAGON is the seven-sided shape and PENTAGON the five-sided one, and both have 8 letters, so they do not fit 7 boxes. Example: the STOP road sign is an oktagon. Watch out: counting the boxes is another way to check your answer.

字谜：顶点 = silang kata: bucu 几条棱相交的那个尖尖的点叫 BUCU（顶点），4 个字母，正方体有 8 个。TEPI 是棱，是线不是点；SISI 是平面图形的边。三个都是 4 个字母，所以要看意思来选。 例子：三角棱柱有 6 个 bucu。 注意：字母数一样时，要靠词的意思判断。

crossword: vertex = silang kata: bucu The pointed corner where several edges meet is a BUCU (vertex), 4 letters, and a cube has 8 of them. TEPI is an edge, a line rather than a point, and SISI is a side of a flat shape. All three have 4 letters, so choose by meaning. Example: a triangular prism has 6 bucu. Watch out: when the letter counts match, decide by what the word means.