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平行线会不会相交 = adakah garis selari bersilang 判断两条线延长后会不会相交，要看它们之间的距离：距离越来越小的线，延长后会碰在一起；距离一直不变的线，就碰不到。回想平行线的定义，想一想它们的距离是怎样的。 例子：两根铁丝一头靠得近、一头离得远，把它们延长，会在靠近的那一头相交。 注意：远处的线看起来好像靠近，只是眼睛的错觉。

do parallel lines meet = adakah garis selari bersilang To decide whether two lines will meet when extended, look at the distance between them: lines that get closer and closer will come together when extended; lines whose distance never changes cannot. Recall the definition of parallel lines and think about their distance. Example: two wires that are close at one end and far apart at the other will meet at the close end if extended. Watch out: lines far away may seem to come together, but that is a trick of the eye.

生活中的垂直线 = garis serenjang dalam kehidupan 垂直线要同时满足两个条件：两条线相交，而且交成直角。把每个选项里的物件想象成两条线，逐个检查这两个条件是否都成立。 例子：墙角的竖线和地板线互相垂直。 注意：两个条件缺一不可。

perpendicular lines in daily life = garis serenjang dalam kehidupan Perpendicular lines must meet two conditions at once: the two lines cross, and they cross at a right angle. Imagine the object in each choice as two lines and check, one by one, whether both conditions hold. Example: the upright line of a wall corner is perpendicular to the floor line. Watch out: both conditions are needed; one alone is not enough.

判断两条线的关系 = hubungan dua garis 先看两条线有没有相交。不相交而且距离一样，是一种关系；相交的话，再看交点上有没有直角记号。斜着画的线也可以互相垂直，不一定要一横一竖。 例子：把一个正方形转一个角度，相邻的两条边仍然互相垂直。 注意：判断时看记号和角，不看线的方向。

how two lines are related = hubungan dua garis First see whether the lines cross. Not crossing and staying the same distance apart is one relationship; if they cross, look for a right-angle mark at the crossing. Slanting lines can be perpendicular too; they need not be one horizontal and one vertical. Example: turn a square at an angle and its neighbouring sides are still perpendicular. Watch out: judge by the marks and angles, not by which way the lines point.

正方形里的平行边 = sisi selari dalam segi empat sama 正方形相对的两条边互相平行，相邻的两条边互相垂直。和指定的边共用一个顶点的边，是相邻的边；没有共用顶点、在它正对面的边，才和它平行。 例子：长方形 ABCD 中，和 AB 垂直的边是 BC 和 DA。 注意：用字母读边时，两个字母是那条边的两个端点。

parallel sides in a square = sisi selari dalam segi empat sama Opposite sides of a square are parallel, and neighbouring sides are perpendicular. A side that shares a vertex with the given side is a neighbour; the side straight across from it, sharing no vertex, is the parallel one. Example: in rectangle ABCD, the sides perpendicular to AB are BC and DA. Watch out: when a side is named by two letters, the letters are its two end points.

平行线的距离 = jarak garis selari 回想平行线的定义：两条平行线之间的距离有什么特点？量两条线之间的距离时，尺子要和线成直角，垂直地量。 例子：量书本上下两条边之间的距离，要把尺子竖直放，和边成直角。 注意：斜着量会量得比较长。

distance between parallel lines = jarak garis selari Recall the definition of parallel lines: what is special about the distance between two parallel lines? When measuring the distance between two lines, hold the ruler at a right angle to them and measure straight across. Example: to measure the distance between the top and bottom edges of a book, stand the ruler upright at a right angle to the edges. Watch out: measuring on a slant gives a longer length.

判断垂直线 = semak garis serenjang 每幅图里，黑线 RS 已经画好，绿线是同学画的。判断方法：先看绿线和 RS 有没有相交（延长也算），再把书角放在交点上，检查交成的角是不是直角。两个条件都符合，才算画对。 例子：用书角沿着横线画出的竖线，和横线之间是直角。 注意：三幅图都要检查，看角而不看线的长短。

checking a perpendicular line = semak garis serenjang In each picture the black line RS is given and the green line was drawn by a pupil. First see whether the green line crosses RS (extending it counts), then put a book corner at the crossing to check whether the angle is a right angle. Only a drawing that meets both conditions is correct. Example: a vertical line drawn along a book corner standing on a horizontal line makes a right angle with it. Watch out: check all three pictures, looking at the angle rather than the line lengths.