题目

Why is good grammar important? Well, good grammar can save lives! Just c【1】 the difference between Let's eat, Grandma! and Let's eat Grandma! With the first one, you are i【2】 your grandma over for a lovely meal. The second one sounds like you are excited about cannibalism (同类相食). Jokes aside, some people think good grammar is not n【3】 They argue that as long as they are being understood, it should not matter w【4】 there are a few grammatical errors or not. But I don't think so. I believe good grammar matters. Thinking about your grammar when you are writing which makes y如图，长度相同的三根轻杆构成一个正三角形支架，在A处固定质量为2m的小球；B处固定质量为m的小球，支架悬挂在O点，可绕过O点与支架所在平面相垂直的固定轴转动.开始时OB与地面相垂直，放手后开始运动.在无任何阻力的情况下，下列说法中正确的是（ ）A．A球到达最低点时速度为零B．B球向左摆动可能达到OB呈水平的位置C．B球向左摆动所能达到的最高位置应高于A球开始运动的高度D．当支架从左向右回摆时，A球能回到起始高度