First, make sure the driver's seat is at a 90-degree angle-not tippedback-to prevent your head from tilting forward, and that both you and your passenger have plenty of legroom.
首先，保证驾驶座呈90度角而不是向后倾斜，以防止你的头倾斜，同时你和你的乘客也有足够的腿部空间。
2
She tipped her head back and laughed loudly.
她把头一仰，哈哈大笑起来。
《牛津词典》
3
Violet Vale was purple with violets and the seedling apple tree far back in the woods was a huge tree peppered over with tiny, crimson-tipped blossom-buds.