我可以用指尖感受到粗糙的纹理。

I could feel the rough texture with the ___tips of my fingers.

削铅笔时要小心，别把笔尖弄断了。

Be careful not to break the sharp ___tip of your pencil when you're sharpening it.

有了现代智能手机，海量知识真的就在你的指尖。

With modern smartphones, vast knowledge is literally at the ___tip of your finger.